Problème de lenteur sur Internet

Bonjour,

Mon PC souffre de problèmes de lenteur quand je suis sur internet. Surement a-t'il attrapé un virus.
Quelqu'un pourrait-il me dire quoi faire ?

Merci d'avance.

Voici le rapport HijackThis :

Logfile of Trend Micro HijackThis v2.0.2
Scan saved at 19:18:19, on 20/12/2008
Platform: Windows Vista SP1 (WinNT 6.00.1905)
MSIE: Internet Explorer v7.00 (7.00.6001.18000)
Boot mode: Normal

Running processes:
C:\Windows\system32\taskeng.exe
C:\Windows\system32\Dwm.exe
C:\Windows\Explorer.EXE
C:\Program Files\Windows Defender\MSASCui.exe
C:\Windows\RtHDVCpl.exe
C:\hp\support\hpsysdrv.exe
C:\Program Files\Hewlett-Packard\On-Screen OSD Indicator\OSD.exe
C:\Windows\System32\rundll32.exe
C:\Program Files\Intel\Intel Matrix Storage Manager\IAAnotif.exe
C:\Program Files\SweetIM\Messenger\SweetIM.exe
C:\Program Files\HP\HP Software Update\hpwuSchd2.exe
C:\Windows\PixArt\Pac207\Monitor.exe
C:\Program Files\Google\Google Desktop Search\GoogleDesktop.exe
C:\Program Files\Windows Sidebar\sidebar.exe
C:\Program Files\Hewlett-Packard\HP Advisor\HPAdvisor.exe
C:\Windows\ehome\ehtray.exe
C:\Program Files\Windows Live\MessengerSearchAddon\msgrsrch.exe
C:\Program Files\Windows Media Player\wmpnscfg.exe
C:\Users\TOUS_LES_4\AppData\Roaming\Microsoft\Live Search\Notification-LiveSearch.exe
C:\Windows\system32\schtasks.exe
C:\Windows\system32\jusched.exe
C:\Windows\System32\rundll32.exe
C:\Windows\ehome\ehmsas.exe
C:\Users\TOUS_LES_4\AppData\Roaming\Microsoft\Live Search\Mise-a-jour-LiveSearch.exe
C:\Program Files\Windows Sidebar\sidebar.exe
C:\Program Files\Google\Google Desktop Search\GoogleDesktop.exe
C:\Windows\system32\conime.exe
C:\hp\kbd\kbd.exe
C:\Windows\system32\taskeng.exe
C:\Windows\system32\sdclt.exe
C:\Program Files\DNA\btdna.exe
C:\Program Files\Windows Media Player\wmplayer.exe
C:\Users\TOUS_LES_4\Downloads\vlc\vlc.exe
C:\Program Files\Internet Explorer\ieuser.exe
C:\Program Files\Internet Explorer\iexplore.exe
C:\Program Files\Common Files\Microsoft Shared\Windows Live\WLLoginProxy.exe
C:\Windows\system32\Macromed\Flash\FlashUtil9f.exe
C:\Downloads\Software\HiJackThis.exe

R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Start Page = https://www.ask.com/?o=101764&l=dis
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Default_Search_URL = https://www.bing.com/?toHttps=1&redig=5FC791212101479BAFBE1A679848B1AF
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Search Page = https://www.bing.com/?toHttps=1&redig=5FC791212101479BAFBE1A679848B1AF
R0 - HKLM\Software\Microsoft\Internet Explorer\Main,Start Page = https://home.sweetim.com/
R0 - HKLM\Software\Microsoft\Internet Explorer\Search,CustomizeSearch =
R0 - HKCU\Software\Microsoft\Internet Explorer\Toolbar,LinksFolderName =
R3 - URLSearchHook: SweetIM ToolbarURLSearchHook Class - {EEE6C35D-6118-11DC-9C72-001320C79847} - C:\Program Files\SweetIM\Toolbars\Internet Explorer\mgHelper.dll
R3 - URLSearchHook: IsoBuster Toolbar - {266fcdca-7bb3-4da7-b3bf-f845dea2ebd6} - C:\Program Files\IsoBuster\tbIsoB.dll
O1 - Hosts: ::1 localhost
O2 - BHO: Aide pour le lien d'Adobe PDF Reader - {06849E9F-C8D7-4D59-B87D-784B7D6BE0B3} - C:\Program Files\Common Files\Adobe\Acrobat\ActiveX\AcroIEHelper.dll
O2 - BHO: AskBar BHO - {201f27d4-3704-41d6-89c1-aa35e39143ed} - C:\Program Files\AskBarDis\bar\bin\askBar.dll
O2 - BHO: IsoBuster Toolbar - {266fcdca-7bb3-4da7-b3bf-f845dea2ebd6} - C:\Program Files\IsoBuster\tbIsoB.dll
O2 - BHO: RealPlayer Download and Record Plugin for Internet Explorer - {3049C3E9-B461-4BC5-8870-4C09146192CA} - C:\Program Files\Real\RealPlayer\rpbrowserrecordplugin.dll
O2 - BHO: SSVHelper Class - {761497BB-D6F0-462C-B6EB-D4DAF1D92D43} - C:\Program Files\Java\jre1.6.0_01\bin\ssv.dll
O2 - BHO: AOL Toolbar Launcher - {7C554162-8CB7-45A4-B8F4-8EA1C75885F9} - C:\Program Files\AOL\AOL Toolbar 5.0\aoltb.dll
O2 - BHO: Programme d'aide de l'Assistant de connexion Windows Live - {9030D464-4C02-4ABF-8ECC-5164760863C6} - C:\Program Files\Common Files\Microsoft Shared\Windows Live\WindowsLiveLogin.dll
O2 - BHO: Google Toolbar Helper - {AA58ED58-01DD-4d91-8333-CF10577473F7} - c:\program files\google\googletoolbar2.dll
O2 - BHO: Windows Live Toolbar Helper - {BDBD1DAD-C946-4A17-ADC1-64B5B4FF55D0} - C:\Program Files\Windows Live Toolbar\msntb.dll
O2 - BHO: FDMIECookiesBHO Class - {CC59E0F9-7E43-44FA-9FAA-8377850BF205} - C:\Program Files\Free Download Manager\iefdm2.dll
O2 - BHO: SWEETIE - {EEE6C35C-6118-11DC-9C72-001320C79847} - C:\Program Files\SweetIM\Toolbars\Internet Explorer\mgToolbarIE.dll
O3 - Toolbar: AOL Toolbar - {DE9C389F-3316-41A7-809B-AA305ED9D922} - C:\Program Files\AOL\AOL Toolbar 5.0\aoltb.dll
O3 - Toolbar: Windows Live Toolbar - {BDAD1DAD-C946-4A17-ADC1-64B5B4FF55D0} - C:\Program Files\Windows Live Toolbar\msntb.dll
O3 - Toolbar: &Google - {2318C2B1-4965-11d4-9B18-009027A5CD4F} - c:\program files\google\googletoolbar2.dll
O3 - Toolbar: SweetIM Toolbar for Internet Explorer - {EEE6C35B-6118-11DC-9C72-001320C79847} - C:\Program Files\SweetIM\Toolbars\Internet Explorer\mgToolbarIE.dll
O3 - Toolbar: IsoBuster Toolbar - {266fcdca-7bb3-4da7-b3bf-f845dea2ebd6} - C:\Program Files\IsoBuster\tbIsoB.dll
O3 - Toolbar: Ask Toolbar - {3041d03e-fd4b-44e0-b742-2d9b88305f98} - C:\Program Files\AskBarDis\bar\bin\askBar.dll
O4 - HKLM\..\Run: [Windows Defender] %ProgramFiles%\Windows Defender\MSASCui.exe -hide
O4 - HKLM\..\Run: [RtHDVCpl] RtHDVCpl.exe
O4 - HKLM\..\Run: [hpsysdrv] c:\hp\support\hpsysdrv.exe
O4 - HKLM\..\Run: [KBD] C:\HP\KBD\KbdStub.EXE
O4 - HKLM\..\Run: [OsdMaestro] "C:\Program Files\Hewlett-Packard\On-Screen OSD Indicator\OSD.exe"
O4 - HKLM\..\Run: [HP Health Check Scheduler] [ProgramFilesFolder]Hewlett-Packard\HP Health Check\HPHC_Scheduler.exe
O4 - HKLM\..\Run: [SunJavaUpdateReg] "C:\Windows\system32\jureg.exe"
O4 - HKLM\..\Run: [Adobe Reader Speed Launcher] "C:\Program Files\Adobe\Reader 8.0\Reader\Reader_sl.exe"
O4 - HKLM\..\Run: [NvSvc] RUNDLL32.EXE C:\Windows\system32\nvsvc.dll,nvsvcStart
O4 - HKLM\..\Run: [NvCplDaemon] RUNDLL32.EXE C:\Windows\system32\NvCpl.dll,NvStartup
O4 - HKLM\..\Run: [NvMediaCenter] RUNDLL32.EXE C:\Windows\system32\NvMcTray.dll,NvTaskbarInit
O4 - HKLM\..\Run: [IAAnotif] "C:\Program Files\Intel\Intel Matrix Storage Manager\Iaanotif.exe"
O4 - HKLM\..\Run: [SweetIM] C:\Program Files\SweetIM\Messenger\SweetIM.exe
O4 - HKLM\..\Run: [WinampAgent] "C:\Program Files\Winamp\winampa.exe"
O4 - HKLM\..\Run: [HP Software Update] C:\Program Files\HP\HP Software Update\HPWuSchd2.exe
O4 - HKLM\..\Run: [Monitor] C:\Windows\PixArt\PAC207\Monitor.exe
O4 - HKLM\..\Run: [Google Desktop Search] "C:\Program Files\Google\Google Desktop Search\GoogleDesktop.exe" /startup
O4 - HKLM\..\Run: [avgnt] "C:\Program Files\Avira\Avira Premium Security Suite\avgnt.exe" /min
O4 - HKCU\..\Run: [Sidebar] C:\Program Files\Windows Sidebar\sidebar.exe
O4 - HKCU\..\Run: [HPAdvisor] C:\Program Files\Hewlett-Packard\HP Advisor\HPAdvisor.exe autorun=AUTORUN
O4 - HKCU\..\Run: [ehTray.exe] C:\Windows\ehome\ehTray.exe
O4 - HKCU\..\Run: [swg] C:\Program Files\Google\GoogleToolbarNotifier\1.2.1128.5462\GoogleToolbarNotifier.exe
O4 - HKCU\..\Run: [msnlivesearch] C:\Program Files\Windows Live\MessengerSearchAddon\msgrsrch.exe /Run
O4 - HKCU\..\Run: [Free Download Manager] "C:\Program Files\Free Download Manager\fdm.exe" -autorun
O4 - HKCU\..\Run: [HijackThis startup scan] C:\Downloads\Software\HijackThis.exe /startupscan
O4 - HKCU\..\Run: [WMPNSCFG] C:\Program Files\Windows Media Player\WMPNSCFG.exe
O4 - HKCU\..\Run: [BitTorrent DNA] "C:\Program Files\DNA\btdna.exe"
O4 - HKCU\..\RunOnce: [Shockwave Updater] C:\Windows\System32\Adobe\SHOCKW~1\SWHELP~1.EXE -Update -1100465 -"Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.0; SIMBAR={D61B7FF6-FDD8-48BB-BDBE-10E6E6C4FF38}; SLCC1; .NET CLR 2.0.50727; Media Center PC 5.0; .NET CLR 3.0.04506; FDM)" -"https://www.habbo.fr/client"
O4 - HKUS\S-1-5-19\..\Run: [Sidebar] %ProgramFiles%\Windows Sidebar\Sidebar.exe /detectMem (User 'SERVICE LOCAL')
O4 - HKUS\S-1-5-19\..\Run: [WindowsWelcomeCenter] rundll32.exe oobefldr.dll,ShowWelcomeCenter (User 'SERVICE LOCAL')
O4 - HKUS\S-1-5-20\..\Run: [Sidebar] %ProgramFiles%\Windows Sidebar\Sidebar.exe /detectMem (User 'SERVICE RÉSEAU')
O4 - Startup: OneNote 2007 - Capture d'écran et lancement.lnk = C:\Program Files\Microsoft Office\Office12\ONENOTEM.EXE
O4 - Startup: Outil de notification Live Search.lnk = C:\Users\TOUS_LES_4\AppData\Roaming\Microsoft\Live Search\Notification-LiveSearch.exe
O8 - Extra context menu item: &Recherche AOL Toolbar - c:\program files\aol\aol toolbar 5.0\resources\fr-fr\local\search.html
O8 - Extra context menu item: &Windows Live Search - res://C:\Program Files\Windows Live Toolbar\msntb.dll/search.htm
O8 - Extra context menu item: Add to Windows &Live Favorites - https://onedrive.live.com/?id=favorites
O8 - Extra context menu item: E&xporter vers Microsoft Excel - res://C:\PROGRA~1\MICROS~3\Office12\EXCEL.EXE/3000
O8 - Extra context menu item: Tout télécharger avec Free Download Manager - file://C:\Program Files\Free Download Manager\dlall.htm
O8 - Extra context menu item: Télécharger avec Free Download Manager - file://C:\Program Files\Free Download Manager\dllink.htm
O8 - Extra context menu item: Télécharger la sélection avec Free Download Manager - file://C:\Program Files\Free Download Manager\dlselected.htm
O8 - Extra context menu item: Télécharger la vidéo avec Free Download Manager - file://C:\Program Files\Free Download Manager\dlfvideo.htm
O9 - Extra button: (no name) - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Program Files\Java\jre1.6.0_01\bin\ssv.dll
O9 - Extra 'Tools' menuitem: Console Java (Sun) - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Program Files\Java\jre1.6.0_01\bin\ssv.dll
O9 - Extra button: Ajout Direct - {219C3416-8CB2-491a-A3C7-D9FCDDC9D600} - C:\Program Files\Windows Live\Writer\WriterBrowserExtension.dll
O9 - Extra 'Tools' menuitem: &Ajout Direct dans Windows Live Writer - {219C3416-8CB2-491a-A3C7-D9FCDDC9D600} - C:\Program Files\Windows Live\Writer\WriterBrowserExtension.dll
O9 - Extra button: Envoyer à OneNote - {2670000A-7350-4f3c-8081-5663EE0C6C49} - C:\PROGRA~1\MICROS~3\Office12\ONBttnIE.dll
O9 - Extra 'Tools' menuitem: &Envoyer à OneNote - {2670000A-7350-4f3c-8081-5663EE0C6C49} - C:\PROGRA~1\MICROS~3\Office12\ONBttnIE.dll
O9 - Extra button: AOL Toolbar - {3369AF0D-62E9-4bda-8103-B4C75499B578} - C:\Program Files\AOL\AOL Toolbar 5.0\aoltb.dll
O9 - Extra button: Research - {92780B25-18CC-41C8-B9BE-3C9C571A8263} - C:\PROGRA~1\MICROS~3\Office12\REFIEBAR.DLL
O13 - Gopher Prefix:
O16 - DPF: CabBuilder - http://kiw.imgag.com/imgag/kiw/toolbar/download/InstallerControl.cab
O16 - DPF: {D27CDB6E-AE6D-11CF-96B8-444553540000} (Shockwave Flash Object) - http://fpdownload2.macromedia.com/get/shockwave/cabs/flash/swflash.cab
O16 - DPF: {D8089245-3211-40F6-819B-9E5E92CD61A2} (FlashXControl Object) - https://signin3.valueactive.eu/Register/Branding/olr3313/OCX/v1018/flashax.cab
O20 - AppInit_DLLs: C:\PROGRA~1\Google\GOOGLE~2\GOEC62~1.DLL
O23 - Service: Avira Premium Security Suite Pare-feu (AntiVirFirewallService) - Avira GmbH - C:\Program Files\Avira\Avira Premium Security Suite\avfwsvc.exe
O23 - Service: Avira Premium Security Suite MailGuard (AntiVirMailService) - Avira GmbH - C:\Program Files\Avira\Avira Premium Security Suite\avmailc.exe
O23 - Service: Planificateur Avira Premium Security Suite (AntiVirScheduler) - Avira GmbH - C:\Program Files\Avira\Avira Premium Security Suite\sched.exe
O23 - Service: Avira Premium Security Suite Guard (AntiVirService) - Avira GmbH - C:\Program Files\Avira\Avira Premium Security Suite\avguard.exe
O23 - Service: Avira Premium Security Suite WebGuard (antivirwebservice) - Avira GmbH - C:\Program Files\Avira\Avira Premium Security Suite\AVWEBGRD.EXE
O23 - Service: Service d'assistance Avira Premium Security Suite MailGuard (AVEService) - Avira GmbH - C:\Program Files\Avira\Avira Premium Security Suite\avesvc.exe
O23 - Service: GameConsoleService - WildTangent, Inc. - C:\Program Files\HP Games\My HP Game Console\GameConsoleService.exe
O23 - Service: Google Desktop Manager 5.7.806.10245 (GoogleDesktopManager-061008-081103) - Google - C:\Program Files\Google\Google Desktop Search\GoogleDesktop.exe
O23 - Service: Google Updater Service (gusvc) - Google - C:\Program Files\Google\Common\Google Updater\GoogleUpdaterService.exe
O23 - Service: HP Health Check Service - Hewlett-Packard - c:\Program Files\Hewlett-Packard\HP Health Check\hphc_service.exe
O23 - Service: Intel(R) Matrix Storage Event Monitor (IAANTMON) - Intel Corporation - C:\Program Files\Intel\Intel Matrix Storage Manager\Iaantmon.exe
O23 - Service: InstallDriver Table Manager (IDriverT) - Macrovision Corporation - C:\Program Files\Common Files\InstallShield\Driver\11\Intel 32\IDriverT.exe
O23 - Service: LightScribeService Direct Disc Labeling Service (LightScribeService) - Hewlett-Packard Company - c:\Program Files\Common Files\LightScribe\LSSrvc.exe