Virus crss.exe help !!!

bonjour a tous et d'avance merci de votre aide.
voila depuis peu mon ordi rame il bloque bref tous les signes d'un virus, en faisant ctrl alt suppr j'ai decouvert ce processus a ppelé "crss.exe" que je n'arrive pas a fermer qui est en fait un virus. Pouvez vous m'aider a le supprimer, je vous post ci joint un log hijackthis. encore merci d'avance.
Logfile of HijackThis v1.99.1
Scan saved at 23:40:04, on 14/11/2001
Platform: Windows XP SP2 (WinNT 5.01.2600)
MSIE: Internet Explorer v6.00 SP2 (6.00.2900.2180)

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:\WINDOWS\system32\spoolsv.exe
C:\Program Files\Alwil Software\Avast4\aswUpdSv.exe
C:\Program Files\Alwil Software\Avast4\ashServ.exe
C:\WINDOWS\system32\svchost.exe
C:\WINDOWS\system32\Ati2evxx.exe
C:\WINDOWS\Explorer.EXE
C:\PROGRA~1\ALWILS~1\Avast4\ashDisp.exe
C:\Program Files\ATI Technologies\ATI.ACE\cli.exe
C:\Program Files\Adobe\Photoshop Album Edition Découverte\3.0\Apps\apdproxy.exe
C:\WINDOWS\system32\svchost.exe
C:\Program Files\Fichiers communs\Microsoft Shared\Works Shared\wkcalrem.exe
C:\Program Files\Alwil Software\Avast4\ashWebSv.exe
C:\WINDOWS\system32\lxcecoms.exe
C:\WINDOWS\system32\WgaTray.exe
C:\Program Files\ATI Technologies\ATI.ACE\cli.exe
C:\Program Files\ATI Technologies\ATI.ACE\cli.exe
C:\WINDOWS\system32\svchost.exe
C:\Program Files\Internet Explorer\iexplore.exe
C:\Program Files\MSN Messenger\msnmsgr.exe
C:\Program Files\Mozilla Firefox\firefox.exe
C:\Documents and Settings\Administrateur\Bureau\HijackThis.exe

R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Search Bar = https://www.bing.com/?cc=fr&toHttps=1&redig=55729C844D6A45819CAD368B3E178C9F
R0 - HKCU\Software\Microsoft\Internet Explorer\Toolbar,LinksFolderName = Liens
O2 - BHO: Adobe PDF Reader Link Helper - {06849E9F-C8D7-4D59-B87D-784B7D6BE0B3} - C:\Program Files\Adobe\Acrobat 7.0\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\jre1.5.0_07\bin\ssv.dll
O2 - BHO: Windows Live Sign-in Helper - {9030D464-4C02-4ABF-8ECC-5164760863C6} - C:\Program Files\Fichiers communs\Microsoft Shared\Windows Live\WindowsLiveLogin.dll
O2 - BHO: ST - {9394EDE7-C8B5-483E-8773-474BF36AF6E4} - C:\Program Files\MSN Apps\ST\01.03.0000.1005\en-xu\stmain.dll
O2 - BHO: MSNToolBandBHO - {BDBD1DAD-C946-4A17-ADC1-64B5B4FF55D0} - C:\Program Files\MSN Apps\MSN Toolbar\01.02.5000.1021\fr\msntb.dll
O3 - Toolbar: &Radio - {8E718888-423F-11D2-876E-00A0C9082467} - C:\WINDOWS\system32\msdxm.ocx
O3 - Toolbar: MSN - {BDAD1DAD-C946-4A17-ADC1-64B5B4FF55D0} - C:\Program Files\MSN Apps\MSN Toolbar\01.02.5000.1021\fr\msntb.dll
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: [ATICCC] "C:\Program Files\ATI Technologies\ATI.ACE\cli.exe" runtime -Delay
O4 - HKLM\..\Run: [LXCECATS] rundll32 C:\WINDOWS\System32\spool\DRIVERS\W32X86\3\LXCEtime.dll,_RunDLLEntry@16
O4 - HKLM\..\Run: [lxcemon.exe] "C:\Program Files\Lexmark 4300 Series\lxcemon.exe"
O4 - HKLM\..\Run: [EzPrint] "C:\Program Files\Lexmark 4300 Series\ezprint.exe"
O4 - HKLM\..\Run: [FaxCenterServer] "C:\Program Files\Lexmark Fax Solutions\fm3032.exe" /s
O4 - HKLM\..\Run: [SunJavaUpdateSched] C:\Program Files\Java\jre1.5.0_07\bin\jusched.exe
O4 - HKLM\..\Run: [Adobe Photo Downloader] "C:\Program Files\Adobe\Photoshop Album Edition Découverte\3.0\Apps\apdproxy.exe"
O4 - HKLM\..\Run: [iTunesHelper] "C:\Program Files\iTunes\iTunesHelper.exe"
O4 - HKLM\..\Run: [QuickTime Task] "C:\Program Files\QuickTime\qttask.exe" -atboottime
O4 - HKLM\..\Run: [.nvsvc] C:\WINDOWS\system\smss.exe /w
O4 - HKLM\..\Run: [TrojanScanner] C:\Program Files\Trojan Remover\Trjscan.exe
O4 - HKCU\..\Run: [MsnMsgr] "C:\Program Files\MSN Messenger\MsnMsgr.Exe" /background
O4 - HKCU\..\Run: [Skype] "C:\Program Files\Skype\Phone\Skype.exe" /nosplash /minimized
O4 - Global Startup: Lancement rapide d'Adobe Reader.lnk = C:\Program Files\Adobe\Acrobat 7.0\Reader\reader_sl.exe
O4 - Global Startup: Rappels du Calendrier Microsoft Works.lnk = ?
O9 - Extra button: (no name) - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Program Files\Java\jre1.5.0_07\bin\ssv.dll
O9 - Extra 'Tools' menuitem: Console Java (Sun) - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Program Files\Java\jre1.5.0_07\bin\ssv.dll
O18 - Protocol: livecall - {828030A1-22C1-4009-854F-8E305202313F} - C:\PROGRA~1\MSNMES~1\MSGRAP~1.DLL
O18 - Protocol: msnim - {828030A1-22C1-4009-854F-8E305202313F} - C:\PROGRA~1\MSNMES~1\MSGRAP~1.DLL
O20 - Winlogon Notify: WgaLogon - C:\WINDOWS\SYSTEM32\WgaLogon.dll
O23 - Service: avast! iAVS4 Control Service (aswUpdSv) - Unknown owner - C:\Program Files\Alwil Software\Avast4\aswUpdSv.exe
O23 - Service: Ati HotKey Poller - ATI Technologies Inc. - C:\WINDOWS\system32\Ati2evxx.exe
O23 - Service: ATI Smart - Unknown owner - C:\WINDOWS\system32\ati2sgag.exe
O23 - Service: avast! Antivirus - Unknown owner - C:\Program Files\Alwil Software\Avast4\ashServ.exe
O23 - Service: avast! Mail Scanner - Unknown owner - C:\Program Files\Alwil Software\Avast4\ashMaiSv.exe" /service (file missing)
O23 - Service: avast! Web Scanner - Unknown owner - C:\Program Files\Alwil Software\Avast4\ashWebSv.exe" /service (file missing)
O23 - Service: InstallDriver Table Manager (IDriverT) - Macrovision Corporation - C:\Program Files\Fichiers communs\InstallShield\Driver\11\Intel 32\IDriverT.exe
O23 - Service: iPodService - Apple Computer, Inc. - C:\Program Files\iPod\bin\iPodService.exe
O23 - Service: lxce_device - Lexmark International, Inc. - C:\WINDOWS\system32\lxcecoms.exe
O23 - Service: SmartLinkService (SLService) - Smart Link - C:\WINDOWS\SYSTEM32\slserv.exe