Probleme de virus

mon PC est viruse. J'ai fait un scan avec Hijack this :

Logfile of HijackThis v1.99.1
Scan saved at 10:58:02 AM, on 09/02/2007
Platform: Windows XP SP2 (WinNT 5.01.2600)
MSIE: Internet Explorer v7.00 (7.00.6000.16512)

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\svchost.exe
C:\WINDOWS\System32\svchost.exe
C:\Program Files\Common Files\Symantec Shared\ccSvcHst.exe
C:\Program Files\Common Files\Symantec Shared\AppCore\AppSvc32.exe
C:\WINDOWS\system32\spoolsv.exe
C:\Program Files\Symantec\LiveUpdate\ALUSchedulerSvc.exe
C:\Program Files\Analog Devices\SoundMAX\SMAgent.exe
C:\Program Files\Common Files\Softwin\BitDefender Communicator\xcommsvr.exe
C:\Program Files\Common Files\Softwin\BitDefender Update Service\livesrv.exe
C:\WINDOWS\Explorer.EXE
C:\Program Files\Common Files\Real\Update_OB\realsched.exe
C:\Program Files\QuickTime\qttask.exe
C:\Program Files\Common Files\Symantec Shared\ccApp.exe
C:\Program Files\DAP\DAP.EXE
C:\Program Files\Softwin\BitDefender10\bdmcon.exe
C:\WINDOWS\System32\svchost.exe
C:\Program Files\Softwin\BitDefender10\bdagent.exe
C:\WINDOWS\system32\ctfmon.exe
C:\Program Files\Metacafe\MetacafeAgent.exe
C:\Program Files\Common Files\Symantec Shared\CCPD-LC\symlcsvc.exe
C:\Program Files\Common Files\Softwin\BitDefender Scan Server\bdss.exe
C:\Program Files\Softwin\BitDefender10\vsserv.exe
C:\Program Files\Metacafe\Metacafe.exe
C:\Program Files\Internet Explorer\iexplore.exe
C:\Documents and Settings\Pierre\Desktop\HijackThis.exe

R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Start Page = https://fr.yahoo.com/
O2 - BHO: Google Toolbar Notifier BHO - {AF69DE43-7D58-4638-B6FA-CE66B5AD205D} - C:\Program Files\Google\GoogleToolbarNotifier\2.0.301.7164\swg.dll
O4 - HKLM\..\Run: [TkBellExe] "C:\Program Files\Common Files\Real\Update_OB\realsched.exe" -osboot
O4 - HKLM\..\Run: [QuickTime Task] "C:\Program Files\QuickTime\qttask.exe" -atboottime
O4 - HKLM\..\Run: [ccApp] "C:\Program Files\Common Files\Symantec Shared\ccApp.exe"
O4 - HKLM\..\Run: [osCheck] "C:\Program Files\Norton AntiVirus\osCheck.exe"
O4 - HKLM\..\Run: [DownloadAccelerator] "C:\Program Files\DAP\DAP.EXE" /STARTUP
O4 - HKLM\..\Run: [Symantec PIF AlertEng] "C:\Program Files\Common Files\Symantec Shared\PIF\{B8E1DD85-8582-4c61-B58F-2F227FCA9A08}\PIFSvc.exe" /a /m "C:\Program Files\Common Files\Symantec Shared\PIF\{B8E1DD85-8582-4c61-B58F-2F227FCA9A08}\AlertEng.dll"
O4 - HKLM\..\Run: [BDMCon] "C:\Program Files\Softwin\BitDefender10\bdmcon.exe" /reg
O4 - HKLM\..\Run: [BDAgent] "C:\Program Files\Softwin\BitDefender10\bdagent.exe"
O4 - HKCU\..\Run: [ctfmon.exe] C:\WINDOWS\system32\ctfmon.exe
O4 - Global Startup: Metacafe.lnk = C:\Program Files\Metacafe\MetacafeAgent.exe
O11 - Options group: [INTERNATIONAL] International*
O20 - Winlogon Notify: WgaLogon - C:\WINDOWS\SYSTEM32\WgaLogon.dll
O21 - SSODL: WPDShServiceObj - {AAA288BA-9A4C-45B0-95D7-94D524869DB5} - C:\WINDOWS\system32\WPDShServiceObj.dll
O23 - Service: BitDefender Scan Server (bdss) - Unknown owner - C:\Program Files\Common Files\Softwin\BitDefender Scan Server\bdss.exe" /service (file missing)
O23 - Service: Symantec Event Manager (ccEvtMgr) - Unknown owner - C:\Program Files\Common Files\Symantec Shared\ccSvcHst.exe" /h ccCommon (file missing)
O23 - Service: Symantec Settings Manager (ccSetMgr) - Unknown owner - C:\Program Files\Common Files\Symantec Shared\ccSvcHst.exe" /h ccCommon (file missing)
O23 - Service: Symantec Lic NetConnect service (CLTNetCnService) - Unknown owner - C:\Program Files\Common Files\Symantec Shared\ccSvcHst.exe" /h ccCommon (file missing)
O23 - Service: InstallDriver Table Manager (IDriverT) - Macrovision Corporation - C:\Program Files\Common Files\InstallShield\Driver\11\Intel 32\IDriverT.exe
O23 - Service: iPodService - Apple Computer, Inc. - C:\Program Files\iPod\bin\iPodService.exe
O23 - Service: Validation de mot de passe Symantec IS (ISPwdSvc) - Symantec Corporation - C:\Program Files\Norton AntiVirus\isPwdSvc.exe
O23 - Service: BitDefender Desktop Update Service (LIVESRV) - Unknown owner - C:\Program Files\Common Files\Softwin\BitDefender Update Service\livesrv.exe" /service (file missing)
O23 - Service: LiveUpdate - Symantec Corporation - C:\PROGRA~1\Symantec\LIVEUP~1\LUCOMS~1.EXE
O23 - Service: LiveUpdate Notice Service Ex (LiveUpdate Notice Ex) - Unknown owner - C:\Program Files\Common Files\Symantec Shared\ccSvcHst.exe" /h ccCommon (file missing)
O23 - Service: LiveUpdate Notice Service - Unknown owner - C:\Program Files\Common Files\Symantec Shared\PIF\{B8E1DD85-8582-4c61-B58F-2F227FCA9A08}\PIFSvc.exe" /m "C:\Program Files\Common Files\Symantec Shared\PIF\{B8E1DD85-8582-4c61-B58F-2F227FCA9A08}\PifEng.dll (file missing)
O23 - Service: Planificateur LiveUpdate automatique - Symantec Corporation - C:\Program Files\Symantec\LiveUpdate\ALUSchedulerSvc.exe
O23 - Service: SoundMAX Agent Service (SoundMAX Agent Service (default)) - Analog Devices, Inc. - C:\Program Files\Analog Devices\SoundMAX\SMAgent.exe
O23 - Service: Symantec Core LC - Symantec Corporation - C:\Program Files\Common Files\Symantec Shared\CCPD-LC\symlcsvc.exe
O23 - Service: Symantec AppCore Service (SymAppCore) - Symantec Corporation - C:\Program Files\Common Files\Symantec Shared\AppCore\AppSvc32.exe
O23 - Service: BitDefender Virus Shield (VSSERV) - Unknown owner - C:\Program Files\Softwin\BitDefender10\vsserv.exe" /service (file missing)
O23 - Service: BitDefender Communicator (XCOMM) - Unknown owner - C:\Program Files\Common Files\Softwin\BitDefender Communicator\xcommsvr.exe" /service (file missing)


que dois je faire ?

Merci