Impossible installer antivirus

Bonjour tout le monde,
j'ai besoin d'aide pour suprimer un virus sur mon pc qui m'empeche d'installer un antivirus. j'ai fait un scan avec hijack et voici le résultat ci-dessous. Please,please aidez moi....
Logfile of HijackThis v1.99.1
Scan saved at 14:47:54, on 15/05/2007
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\svchost.exe
C:\WINDOWS\System32\svchost.exe
C:\WINDOWS\system32\spoolsv.exe
C:\Program Files\Fichiers communs\Microsoft Shared\VS7Debug\mdm.exe
C:\WINDOWS\System32\nvsvc32.exe
C:\WINDOWS\System32\HPZipm12.exe
C:\Program Files\Alcohol Soft\Alcohol 120\StarWind\StarWindService.exe
C:\WINDOWS\System32\svchost.exe
C:\WINDOWS\system32\WgaTray.exe
C:\WINDOWS\Explorer.EXE
C:\WINDOWS\system32\ctfmon.exe
C:\Program Files\Messenger\msmsgs.exe
C:\Program Files\Mozilla Firefox\firefox.exe
C:\Program Files\Google\Common\Google Updater\GoogleUpdaterService.exe
C:\Program Files\Google\Google Updater\GoogleUpdater.exe
C:\Program Files\Google\Google Updater\GoogleUpdater.exe
C:\Program Files\Google\Google Updater\2.1.850.19570\GoogleUpdaterInstallMgr.exe
C:\Program Files\Google\Google Desktop Search\GoogleDesktop.exe
C:\Program Files\Google\Google Desktop Search\GoogleDesktop.exe
C:\Program Files\Google\Google Desktop Search\GoogleDesktop.exe
C:\Program Files\Spyware Doctor\swdsvc.exe
C:\Program Files\Spyware Doctor\svcntaux.exe
C:\Program Files\Spyware Doctor\sdtrayapp.exe
C:\Documents and Settings\All Users\Application Data\Google Updater\cache\installers_ci_sd_en_5.0.0.184_setup_2007.05.11_11.02.32.exe
C:\DOCUME~1\yass\LOCALS~1\Temp\is-SL8D7.tmp\is-8CCU3.tmp
C:\Documents and Settings\yass\Mes documents\Hijackthis\HijackThis.exe

R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Start Page = https://www.msn.com/fr-fr
R0 - HKLM\Software\Microsoft\Internet Explorer\Main,Start Page = https://home.sweetim.com/
R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Local Page =
R0 - HKLM\Software\Microsoft\Internet Explorer\Main,Local Page =
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
O1 - Hosts: 127.255.255.255 serial.alcohol-soft.com
O1 - Hosts: 127.255.255.255 www.alcohol-soft.com
O1 - Hosts: 127.255.255.255 images.alcohol-soft.com
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: Skype add-on (mastermind) - {22BF413B-C6D2-4d91-82A9-A0F997BA588C} - C:\PROGRA~1\Skype\Phone\IEPlugin\SKYPEI~1.DLL
O2 - BHO: SSVHelper Class - {761497BB-D6F0-462C-B6EB-D4DAF1D92D43} - C:\Program Files\Java\jre1.5.0_11\bin\ssv.dll
O2 - BHO: (no name) - {7E853D72-626A-48EC-A868-BA8D5E23E045} - (no file)
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: Google Toolbar Helper - {AA58ED58-01DD-4d91-8333-CF10577473F7} - c:\program files\google\googletoolbar3.dll
O2 - BHO: Google Toolbar Notifier BHO - {AF69DE43-7D58-4638-B6FA-CE66B5AD205D} - C:\Program Files\Google\GoogleToolbarNotifier\2.0.301.5672\swg.dll
O3 - Toolbar: &Google - {2318C2B1-4965-11d4-9B18-009027A5CD4F} - c:\program files\google\googletoolbar3.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: [NvCplDaemon] RUNDLL32.EXE C:\WINDOWS\system32\NvCpl.dll,NvStartup
O4 - HKLM\..\Run: [avast!] C:\PROGRA~1\ALWILS~1\Avast4\ashDisp.exe
O4 - HKLM\..\Run: [Google Desktop Search] "C:\Program Files\Google\Google Desktop Search\GoogleDesktop.exe" /startup
O4 - HKLM\..\Run: [SDTray] "C:\Program Files\Spyware Doctor\SDTrayApp.exe"
O4 - HKCU\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\ctfmon.exe
O4 - HKCU\..\Run: [MSMSGS] "C:\Program Files\Messenger\msmsgs.exe" /background
O4 - HKCU\..\Run: [eMuleAutoStart] C:\Program Files\eMule\emule.exe -AutoStart
O4 - HKCU\..\Run: [swg] C:\Program Files\Google\GoogleToolbarNotifier\GoogleToolbarNotifier.exe
O4 - Global Startup: Microsoft Office.lnk = C:\Program Files\Microsoft Office\Office10\OSA.EXE
O4 - Global Startup: Outil de mise à jour Google.lnk = C:\Program Files\Google\Google Updater\GoogleUpdater.exe
O8 - Extra context menu item: E&xport to Microsoft Excel - res://C:\PROGRA~1\MICROS~2\Office12\EXCEL.EXE/3000
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\jre1.5.0_11\bin\ssv.dll
O9 - Extra 'Tools' menuitem: Console Java (Sun) - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Program Files\Java\jre1.5.0_11\bin\ssv.dll
O9 - Extra button: Skype - {77BF5300-1474-4EC7-9980-D32B190E9B07} - C:\PROGRA~1\Skype\Phone\IEPlugin\SKYPEI~1.DLL
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
O16 - DPF: {17492023-C23A-453E-A040-C7C580BBF700} (Windows Genuine Advantage Validation Tool) - http://download.microsoft.com/download/E/5/6/E5611B10-0D6D-4117-8430-A67417AA88CD/LegitCheckControl.cab
O16 - DPF: {1D4DB7D2-6EC9-47A3-BD87-1E41684E07BB} - http://ak.exe.imgfarm.com/images/nocache/funwebproducts/ei/SmileyCentralFWBInitialSetup1.0.0.15-3.cab
O16 - DPF: {30528230-99f7-4bb4-88d8-fa1d4f56a2ab} (YInstStarter Class) - C:\Program Files\Yahoo!\Common\yinsthelper.dll
O16 - DPF: {4F1E5B1A-2A80-42CA-8532-2D05CB959537} (MSN Photo Upload Tool) - http://by119fd.bay119.hotmail.msn.com/resources/MsnPUpld.cab
O16 - DPF: {55027008-315F-4F45-BBC3-8BE119764741} (Slide Image Uploader Control) - http://www.slide.com/uploader/SlideImageUploader.cab
O16 - DPF: {56336BCB-3D8A-11D6-A00B-0050DA18DE71} (RdxIE Class) - http://software-dl.real.com/09845aab99d1d6aefc19/netzip/RdxIE601_fr.cab
O16 - DPF: {CE69F98F-2AF3-4306-BAC6-A79070EDA1B4} (Zylom Loader Object) - http://eu.download.games.yahoo.com/zylom/activex/zylomloader.cab
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
O18 - Protocol: skype4com - {FFC8B962-9B40-4DFF-9458-1830C7DD7F5D} - C:\PROGRA~1\FICHIE~1\Skype\SKYPE4~1.DLL
O20 - AppInit_DLLs: C:\PROGRA~1\Google\GOOGLE~1\GOEC62~1.DLL
O20 - Winlogon Notify: WgaLogon - C:\WINDOWS\SYSTEM32\WgaLogon.dll
O23 - Service: AVG Anti-Spyware Guard - Unknown owner - (no file)
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: InstallDriver Table Manager (IDriverT) - Macrovision Corporation - C:\Program Files\Fichiers communs\InstallShield\Driver\11\Intel 32\IDriverT.exe
O23 - Service: NVIDIA Display Driver Service (NVSvc) - NVIDIA Corporation - C:\WINDOWS\System32\nvsvc32.exe
O23 - Service: Pml Driver HPZ12 - HP - C:\WINDOWS\System32\HPZipm12.exe
O23 - Service: SiSoftware Database Agent Service (SandraDataSrv) - SiSoftware - C:\Program Files\SiSoftware\SiSoftware Sandra Lite XI.SP1a\Win32\RpcDataSrv.exe
O23 - Service: SiSoftware Sandra Agent Service (SandraTheSrv) - SiSoftware - C:\Program Files\SiSoftware\SiSoftware Sandra Lite XI.SP1a\RpcSandraSrv.exe
O23 - Service: Spyware Doctor Auxiliary Service (sdAuxService) - PC Tools - C:\Program Files\Spyware Doctor\svcntaux.exe
O23 - Service: Spyware Doctor Service (sdCoreService) - PC Tools - C:\Program Files\Spyware Doctor\swdsvc.exe
O23 - Service: StarWind iSCSI Service (StarWindService) - Rocket Division Software - C:\Program Files\Alcohol Soft\Alcohol 120\StarWind\StarWindService.exe