Système très lent

Salut,

J'ai un petit souci avec Windows XP pro. Depuis un mois, il est très très lent à exécuter certaines tâches, en particulier VLC, Firefox et PinnaclePCTV Vision. C'est aussi le cas au démarrage et à la fermeture. J'ai déjà scanné contre les virus, aucun problème de ce côté. J'ai défragmenté aussi, tout est parfait. Idem avec psybot. J'ai parfois l'impression qu'il est encore plus lent quand il a besoin de se connecter au net (par FreeBox).

Voici le rapport Hijackthis :

Logfile of Trend Micro HijackThis v2.0.2
Scan saved at 17:54:27, on 17/01/2008
Platform: Windows XP SP2 (WinNT 5.01.2600)
MSIE: Internet Explorer v7.00 (7.00.6000.16574)
Boot mode: Normal

Running processes:
C:\WINDOWS\System32\smss.exe
C:\WINDOWS\system32\winlogon.exe
C:\WINDOWS\system32\services.exe
C:\WINDOWS\system32\lsass.exe
C:\WINDOWS\system32\Ati2evxx.exe
C:\WINDOWS\system32\svchost.exe
C:\WINDOWS\System32\svchost.exe
C:\Program Files\Alwil Software\Avast4\aswUpdSv.exe
C:\Program Files\Alwil Software\Avast4\ashServ.exe
C:\WINDOWS\system32\Ati2evxx.exe
C:\WINDOWS\Explorer.EXE
C:\PROGRA~1\ALWILS~1\Avast4\ashDisp.exe
C:\Program Files\Startup Mechanic\StartupMonitor.exe
C:\Program Files\Pinnacle\Pinnacle PCTV\Remote\Remoterm.exe
C:\Program Files\ScanSoft\PaperPort\pptd40nt.exe
C:\Program Files\RALINK\Common\RaUI.exe
C:\WINDOWS\System32\brsvc01a.exe
C:\WINDOWS\System32\brss01a.exe
C:\WINDOWS\system32\spoolsv.exe
C:\WINDOWS\System32\svchost.exe
C:\Program Files\Alwil Software\Avast4\ashMaiSv.exe
C:\Program Files\Alwil Software\Avast4\ashWebSv.exe
D:\eMule\emule.exe
C:\WINDOWS\system32\ctfmon.exe
C:\Program Files\Brother\Brmfcmon\brmfcwnd.exe
C:\Program Files\Brother\Brmfcmon\BrMfimon.exe
C:\PROGRA~1\Pinnacle\SHARED~1\Filter\server.exe
C:\Program Files\Pinnacle\Shared Files\Programs\Scheduler\PCLEScheduler.exe
C:\WINDOWS\system32\taskmgr.exe
C:\Program Files\Yahoo!\Widgets\YahooWidgets.exe
C:\Program Files\Yahoo!\Widgets\YahooWidgets.exe
C:\Program Files\Yahoo!\Widgets\YahooWidgets.exe
C:\Program Files\Yahoo!\Widgets\YahooWidgets.exe
C:\Program Files\Yahoo!\Widgets\YahooWidgets.exe
C:\Program Files\Yahoo!\Widgets\YahooWidgets.exe
C:\Program Files\Yahoo!\Widgets\YahooWidgets.exe
C:\Program Files\Yahoo!\Widgets\YahooWidgets.exe
C:\Program Files\Yahoo!\Widgets\YahooWidgets.exe
D:\fox\Foxmail.exe
C:\Program Files\Mozilla Firefox\firefox.exe
C:\Program Files\Pinnacle\Pinnacle PCTV\Vision\Vision.exe
C:\PROGRA~1\Pinnacle\SHARED~1\Filter\VBI_SE~1.EXE
C:\Program Files\Trend Micro\HijackThis\HijackThis.exe

R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Start Page = https://www.google.fr/?gws_rd=ssl
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Default_Page_URL = https://www.msn.com/fr-fr/?ocid=iehp
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://www.msn.com/fr-fr/?ocid=iehp
R0 - HKCU\Software\Microsoft\Internet Explorer\Toolbar,LinksFolderName = Liens
R3 - URLSearchHook: Yahoo! Toolbar avec bloqueur de fenêtres pop-up - {EF99BD32-C1FB-11D2-892F-0090271D4F88} - C:\Program Files\Yahoo!\Companion\Installs\cpn\yt.dll
O2 - BHO: Yahoo! Toolbar Helper - {02478D38-C3F9-4EFB-9B51-7695ECA05670} - C:\Program Files\Yahoo!\Companion\Installs\cpn\yt.dll
O2 - BHO: Aide pour le lien d'Adobe PDF Reader - {06849E9F-C8D7-4D59-B87D-784B7D6BE0B3} - C:\Program Files\Fichiers communs\Adobe\Acrobat\ActiveX\AcroIEHelper.dll
O2 - BHO: (no name) - {53707962-6F74-2D53-2644-206D7942484F} - C:\PROGRA~1\SPYBOT~1\SDHelper.dll
O2 - BHO: SSVHelper Class - {761497BB-D6F0-462C-B6EB-D4DAF1D92D43} - C:\Program Files\Java\jre1.6.0_02\bin\ssv.dll
O2 - BHO: (no name) - {7E853D72-626A-48EC-A868-BA8D5E23E045} - (no file)
O3 - Toolbar: Yahoo! Toolbar avec bloqueur de fenêtres pop-up - {EF99BD32-C1FB-11D2-892F-0090271D4F88} - C:\Program Files\Yahoo!\Companion\Installs\cpn\yt.dll
O4 - HKLM\..\Run: [avast!] C:\PROGRA~1\ALWILS~1\Avast4\ashDisp.exe
O4 - HKLM\..\Run: [Startup Manager Scanner] C:\Program Files\Startup Mechanic\StartupMonitor.exe
O4 - HKLM\..\Run: [PCTVRemote] C:\Program Files\Pinnacle\Pinnacle PCTV\Remote\Remoterm.exe
O4 - HKLM\..\Run: [PCLEPCI] C:\PROGRA~1\Pinnacle\PPE\PPE.EXE
O4 - HKLM\..\Run: [PaperPort PTD] C:\Program Files\ScanSoft\PaperPort\pptd40nt.exe
O4 - HKLM\..\Run: [IndexSearch] C:\Program Files\ScanSoft\PaperPort\IndexSearch.exe
O4 - HKLM\..\Run: [ControlCenter2.0] C:\Program Files\Brother\ControlCenter2\brctrcen.exe /autorun
O4 - HKUS\S-1-5-19\..\Run: [CTFMON.EXE] C:\WINDOWS\System32\CTFMON.EXE (User 'SERVICE LOCAL')
O4 - HKUS\S-1-5-20\..\Run: [CTFMON.EXE] C:\WINDOWS\System32\CTFMON.EXE (User 'SERVICE RÉSEAU')
O4 - Startup: Yahoo! Widgets.lnk = C:\Program Files\Yahoo!\Widgets\YahooWidgets.exe
O4 - Global Startup: Contrôleur d’état.lnk = C:\Program Files\Brother\Brmfcmon\BrMfcWnd.exe
O4 - Global Startup: Ralink Wireless Utility.lnk = C:\Program Files\RALINK\Common\RaUI.exe
O8 - Extra context menu item: E&xporter vers Microsoft Excel - res://C:\PROGRA~1\MICROS~2\Office10\EXCEL.EXE/3000
O9 - Extra button: (no name) - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Program Files\Java\jre1.6.0_02\bin\ssv.dll
O9 - Extra 'Tools' menuitem: Console Java (Sun) - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Program Files\Java\jre1.6.0_02\bin\ssv.dll
O9 - Extra button: (no name) - {e2e2dd38-d088-4134-82b7-f2ba38496583} - C:\WINDOWS\Network Diagnostic\xpnetdiag.exe
O9 - Extra 'Tools' menuitem: @xpsp3res.dll,-20001 - {e2e2dd38-d088-4134-82b7-f2ba38496583} - C:\WINDOWS\Network Diagnostic\xpnetdiag.exe
O9 - Extra button: Messenger - {FB5F1910-F110-11d2-BB9E-00C04F795683} - C:\Program Files\Messenger\msmsgs.exe
O9 - Extra 'Tools' menuitem: Windows Messenger - {FB5F1910-F110-11d2-BB9E-00C04F795683} - C:\Program Files\Messenger\msmsgs.exe
O12 - Plugin for .spop: C:\Program Files\Internet Explorer\Plugins\NPDocBox.dll
O16 - DPF: {30528230-99f7-4bb4-88d8-fa1d4f56a2ab} (Installation Support) - C:\Program Files\Yahoo!\Common\Yinsthelper.dll
O16 - DPF: {6414512B-B978-451D-A0D8-FCFDF33E833C} (WUWebControl Class) - http://www.update.microsoft.com/...
O16 - DPF: {D27CDB6E-AE6D-11CF-96B8-444553540000} (Shockwave Flash Object) - http://fpdownload2.macromedia.com/get/shockwave/cabs/flash/swflash.cab
O17 - HKLM\System\CCS\Services\Tcpip\..\{19302A78-A2A3-4572-A023-A9290E6398EB}: NameServer = 212.27.54.252,212.27.53.252
O17 - HKLM\System\CS1\Services\Tcpip\..\{19302A78-A2A3-4572-A023-A9290E6398EB}: NameServer = 212.27.54.252,212.27.53.252
O17 - HKLM\System\CS2\Services\Tcpip\..\{19302A78-A2A3-4572-A023-A9290E6398EB}: NameServer = 212.27.54.252,212.27.53.252
O20 - AppInit_DLLs: C:\PROGRA~1\Google\GOOGLE~3\GOEC62~1.DLL
O23 - Service: avast! iAVS4 Control Service (aswUpdSv) - ALWIL Software - C:\Program Files\Alwil Software\Avast4\aswUpdSv.exe
O23 - Service: Ati HotKey Poller - ATI Technologies Inc. - C:\WINDOWS\system32\Ati2evxx.exe
O23 - Service: avast! Antivirus - ALWIL Software - C:\Program Files\Alwil Software\Avast4\ashServ.exe
O23 - Service: avast! Mail Scanner - ALWIL Software - C:\Program Files\Alwil Software\Avast4\ashMaiSv.exe
O23 - Service: avast! Web Scanner - ALWIL Software - C:\Program Files\Alwil Software\Avast4\ashWebSv.exe
O23 - Service: BrSplService (Brother XP spl Service) - brother Industries Ltd - C:\WINDOWS\System32\brsvc01a.exe
O23 - Service: GoogleDesktopManager - 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: Remote Packet Capture Protocol v.0 (experimental) (rpcapd) - CACE Technologies - C:\Program Files\WinPcap\rpcapd.exe