Probleme de lenteur pc

Bonjour,
J'ai un sérieux problème récent de lenteur avec mon PC, très très lent et souvent plantage explorateur windows.
AMD Athlon, RAM 256 Mo, Windows PC
Si quelqu'un pouvait m'aider, je suis une bille en informatique!!!
Ci-dessous le rapport Hijackthis, visiblement ça peut aider l'informaticien averti...
Merci d'avance

Logfile of Trend Micro HijackThis v2.0.2
Scan saved at 18:17:23, on 16/02/2008
Platform: Windows XP SP2 (WinNT 5.01.2600)
MSIE: Internet Explorer v7.00 (7.00.6000.16608)
Boot mode: Normal

Running processes:
D:\WINDOWS\System32\smss.exe
D:\WINDOWS\system32\csrss.exe
D:\WINDOWS\system32\winlogon.exe
D:\WINDOWS\system32\services.exe
D:\WINDOWS\system32\lsass.exe
D:\WINDOWS\system32\svchost.exe
D:\WINDOWS\system32\svchost.exe
D:\WINDOWS\System32\svchost.exe
D:\WINDOWS\system32\svchost.exe
D:\WINDOWS\system32\svchost.exe
D:\WINDOWS\Explorer.EXE
D:\Program Files\Alwil Software\Avast4\aswUpdSv.exe
D:\Program Files\Alwil Software\Avast4\ashServ.exe
D:\WINDOWS\system32\spoolsv.exe
D:\Program Files\Fichiers communs\Apple\Mobile Device Support\bin\AppleMobileDeviceService.exe
D:\WINDOWS\System32\FTRTSVC.exe
D:\WINDOWS\system32\RunDll32.exe
D:\Program Files\CyberLink\PowerDVD\PDVDServ.exe
D:\PROGRA~1\ALWILS~1\Avast4\ashDisp.exe
D:\Program Files\Creative\Shared Files\CIDS\CTStray.exe
D:\Program Files\CyberLink\Shared Files\RichVideo.exe
D:\WINDOWS\System32\spool\DRIVERS\W32X86\3\E_S4I0K2.EXE
D:\WINDOWS\system32\svchost.exe
D:\WINDOWS\system32\wdfmgr.exe
D:\Program Files\Fichiers communs\ACD Systems\FR\DevDetect.exe
D:\PROGRA~1\Wanadoo\TaskBarIcon.exe
D:\Program Files\Logitech\Video\LogiTray.exe
D:\Program Files\iTunes\iTunesHelper.exe
D:\WINDOWS\system32\ctfmon.exe
D:\Program Files\Fichiers communs\Ahead\Lib\NMBgMonitor.exe
D:\Program Files\SuperCopier2\SuperCopier2.exe
D:\PROGRA~1\Wanadoo\EspaceWanadoo.exe
D:\Program Files\Fichiers communs\Ahead\Lib\NMIndexStoreSvr.exe
D:\PROGRA~1\Wanadoo\ComComp.exe
D:\Program Files\SAGEM WiFi manager\WLANUTL.exe
D:\PROGRA~1\Wanadoo\Toaster.exe
D:\PROGRA~1\Wanadoo\Inactivity.exe
D:\PROGRA~1\Wanadoo\PollingModule.exe
D:\WINDOWS\System32\ALERTM~1\ALERTM~1.EXE
D:\Program Files\Alwil Software\Avast4\ashMaiSv.exe
D:\Program Files\Alwil Software\Avast4\ashWebSv.exe
D:\Program Files\Fichiers communs\Ahead\Lib\NMIndexingService.exe
D:\WINDOWS\System32\alg.exe
D:\Program Files\iPod\bin\iPodService.exe
D:\PROGRA~1\Wanadoo\Watch.exe
D:\Program Files\Internet Explorer\IEXPLORE.EXE
D:\Program Files\WinRAR\WinRAR.exe
D:\DOCUME~1\Barbe\LOCALS~1\Temp\Rar$EX01.609\HijackThis.exe
D:\WINDOWS\system32\wbem\wmiprvse.exe

R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Search Bar = https://www.orange.fr/portail
R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Start Page = https://www.orange.fr/portail
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
R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Window Title = Wanadoo
R0 - HKCU\Software\Microsoft\Internet Explorer\Toolbar,LinksFolderName = Liens
R3 - URLSearchHook: Search Class - {08C06D61-F1F3-4799-86F8-BE1A89362C85} - D:\PROGRA~1\Wanadoo\SEARCH~1.DLL
O2 - BHO: Aide pour le lien d'Adobe PDF Reader - {06849E9F-C8D7-4D59-B87D-784B7D6BE0B3} - D:\Program Files\Fichiers communs\Adobe\Acrobat\ActiveX\AcroIEHelper.dll
O4 - HKLM\..\Run: [SiSUSBRG] D:\WINDOWS\SiSUSBrg.exe
O4 - HKLM\..\Run: [Cmaudio] RunDll32 cmicnfg.cpl,CMICtrlWnd
O4 - HKLM\..\Run: [RemoteControl] "D:\Program Files\CyberLink\PowerDVD\PDVDServ.exe"
O4 - HKLM\..\Run: [LanguageShortcut] "D:\Program Files\CyberLink\PowerDVD\Language\Language.exe"
O4 - HKLM\..\Run: [NeroFilterCheck] D:\Program Files\Fichiers communs\Ahead\Lib\NeroCheck.exe
O4 - HKLM\..\Run: [Adobe Reader Speed Launcher] "D:\Program Files\Adobe\Reader 8.0\Reader\Reader_sl.exe"
O4 - HKLM\..\Run: [WOOWATCH] D:\PROGRA~1\Wanadoo\Watch.exe
O4 - HKLM\..\Run: [WOOTASKBARICON] D:\PROGRA~1\Wanadoo\GestMaj.exe TaskBarIcon.exe
O4 - HKLM\..\Run: [avast!] D:\PROGRA~1\ALWILS~1\Avast4\ashDisp.exe
O4 - HKLM\..\Run: [Creative Mouse Software] D:\Program Files\Creative\Shared Files\CIDS\CTStray.exe
O4 - HKLM\..\Run: [EPSON Stylus Photo RX500] D:\WINDOWS\System32\spool\DRIVERS\W32X86\3\E_S4I0K2.EXE /P24 "EPSON Stylus Photo RX500" /O6 "USB001" /M "Stylus Photo RX500"
O4 - HKLM\..\Run: [Device Detector] "D:\Program Files\Fichiers communs\ACD Systems\FR\DevDetect.exe" -autorun
O4 - HKLM\..\Run: [LogitechVideoRepair] D:\Program Files\Logitech\Video\ISStart.exe
O4 - HKLM\..\Run: [LogitechVideoTray] D:\Program Files\Logitech\Video\LogiTray.exe
O4 - HKLM\..\Run: [QuickTime Task] "D:\Program Files\QuickTime\qttask.exe" -atboottime
O4 - HKLM\..\Run: [iTunesHelper] "D:\Program Files\iTunes\iTunesHelper.exe"
O4 - HKCU\..\Run: [CTFMON.EXE] D:\WINDOWS\system32\ctfmon.exe
O4 - HKCU\..\Run: [BgMonitor_{79662E04-7C6C-4d9f-84C7-88D8A56B10AA}] "D:\Program Files\Fichiers communs\Ahead\Lib\NMBgMonitor.exe"
O4 - HKCU\..\Run: [SuperCopier2.exe] D:\Program Files\SuperCopier2\SuperCopier2.exe
O4 - HKCU\..\Run: [WOOKIT] D:\PROGRA~1\Wanadoo\Shell.exe appLaunchClientZone.shl|DEFAULT=cnx|PARAM=
O4 - HKUS\S-1-5-19\..\Run: [CTFMON.EXE] D:\WINDOWS\system32\CTFMON.EXE (User 'SERVICE LOCAL')
O4 - HKUS\S-1-5-20\..\Run: [CTFMON.EXE] D:\WINDOWS\system32\CTFMON.EXE (User 'SERVICE RÉSEAU')
O4 - HKUS\S-1-5-18\..\Run: [CTFMON.EXE] D:\WINDOWS\system32\CTFMON.EXE (User 'SYSTEM')
O4 - HKUS\.DEFAULT\..\Run: [CTFMON.EXE] D:\WINDOWS\system32\CTFMON.EXE (User 'Default user')
O4 - Global Startup: Adobe Gamma Loader.lnk = D:\Program Files\Fichiers communs\Adobe\Calibration\Adobe Gamma Loader.exe
O4 - Global Startup: Logitech Desktop Messenger.lnk = D:\Program Files\Logitech\Desktop Messenger\8876480\Program\LDMConf.exe
O4 - Global Startup: Microsoft Office.lnk = D:\Program Files\Microsoft Office\Office10\OSA.EXE
O4 - Global Startup: Utilitaire réseau pour SAGEM Wi-Fi 11g USB adapter.lnk = ?
O8 - Extra context menu item: E&xporter vers Microsoft Excel - res://D:\PROGRA~1\MICROS~2\Office10\EXCEL.EXE/3000
O9 - Extra button: (no name) - {e2e2dd38-d088-4134-82b7-f2ba38496583} - D:\WINDOWS\Network Diagnostic\xpnetdiag.exe
O9 - Extra 'Tools' menuitem: @xpsp3res.dll,-20001 - {e2e2dd38-d088-4134-82b7-f2ba38496583} - D:\WINDOWS\Network Diagnostic\xpnetdiag.exe
O9 - Extra button: Messager Wanadoo - {FB5F1910-F110-11d2-BB9E-00C04F795683} - D:\PROGRA~1\WANADO~1\Wanadoo Messager.exe
O9 - Extra 'Tools' menuitem: Messager Wanadoo - {FB5F1910-F110-11d2-BB9E-00C04F795683} - D:\PROGRA~1\WANADO~1\Wanadoo Messager.exe
O9 - Extra button: Wanadoo - {1462651F-F4BA-4C76-A001-C4284D0FE16E} - https://www.orange.fr/portail (file missing) (HKCU)
O16 - DPF: {D27CDB6E-AE6D-11CF-96B8-444553540000} (Shockwave Flash Object) - http://fpdownload2.macromedia.com/get/shockwave/cabs/flash/swflash.cab
O23 - Service: Apple Mobile Device - Apple, Inc. - D:\Program Files\Fichiers communs\Apple\Mobile Device Support\bin\AppleMobileDeviceService.exe
O23 - Service: avast! iAVS4 Control Service (aswUpdSv) - ALWIL Software - D:\Program Files\Alwil Software\Avast4\aswUpdSv.exe
O23 - Service: avast! Antivirus - ALWIL Software - D:\Program Files\Alwil Software\Avast4\ashServ.exe
O23 - Service: avast! Mail Scanner - ALWIL Software - D:\Program Files\Alwil Software\Avast4\ashMaiSv.exe
O23 - Service: avast! Web Scanner - ALWIL Software - D:\Program Files\Alwil Software\Avast4\ashWebSv.exe
O23 - Service: France Telecom Routing Table Service (FTRTSVC) - France Telecom - D:\WINDOWS\System32\FTRTSVC.exe
O23 - Service: InstallDriver Table Manager (IDriverT) - Macrovision Corporation - D:\Program Files\Fichiers communs\InstallShield\Driver\11\Intel 32\IDriverT.exe
O23 - Service: Service de l'iPod (iPod Service) - Apple Inc. - D:\Program Files\iPod\bin\iPodService.exe
O23 - Service: NMIndexingService - Nero AG - D:\Program Files\Fichiers communs\Ahead\Lib\NMIndexingService.exe
O23 - Service: Cyberlink RichVideo Service(CRVS) (RichVideo) - Unknown owner - D:\Program Files\CyberLink\Shared Files\RichVideo.exe