Win32 a l'aide

je suis nouveau sur ce site et j'ai un petit problème assez embêtant...: mon pc redémare tout seul tout le temps, ne repère plus ma carte son & d'otres inconveniant. Après quelques recherches il s'avère que c a cause de Win32, vu que je ne m'y connais que très peu en matière d'informatique, est-ce que quelqu'un pourais me donné un coup de main svp???
merci d'avance.
voici déja le resultat du scan fais avec "Hijackthis":

Logfile of HijackThis v1.99.1
Scan saved at 02:03:25, on 24/02/2007
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\Explorer.EXE
C:\WINDOWS\system32\spoolsv.exe
C:\Program Files\Alwil Software\Avast4\aswUpdSv.exe
C:\Program Files\Alwil Software\Avast4\ashServ.exe
C:\WINDOWS\eHome\ehRecvr.exe
C:\WINDOWS\eHome\ehSched.exe
C:\WINDOWS\ehome\ehtray.exe
C:\Program Files\MessengerPlus! 3\MsgPlus.exe
C:\PROGRA~1\ALWILS~1\Avast4\ashDisp.exe
C:\Program Files\Messenger\msmsgs.exe
C:\Program Files\BitTorrent\bittorrent.exe
C:\Program Files\Google\GoogleToolbarNotifier\1.2.1128.5462\GoogleToolbarNotifier.exe
C:\Program Files\MSN Messenger\msnmsgr.exe
C:\Program Files\WinZip\WZQKPICK.EXE
C:\WINDOWS\system32\dllhost.exe
C:\WINDOWS\eHome\ehmsas.exe
C:\WINDOWS\System32\svchost.exe
C:\Program Files\MSN Messenger\usnsvc.exe
C:\Program Files\Internet Explorer\IEXPLORE.EXE
C:\Program Files\Fichiers communs\Microsoft Shared\Windows Live\WLLoginProxy.exe
C:\Program Files\a-squared Free\a2free.exe
C:\Documents and Settings\Administrateur.MCE2005.001\Bureau\HijackThis.exe

R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Start Page = https://www.google.ch/?gws_rd=ssl
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Default_Page_URL = http://internet.sunrise.ch/fr/hom/default.asp
R0 - HKLM\Software\Microsoft\Internet Explorer\Main,Start Page = https://www.google.ch/?gws_rd=ssl
O2 - BHO: (no name) - {02478D38-C3F9-4EFB-9B51-7695ECA05670} - (no file)
O2 - BHO: AcroIEHlprObj Class - {06849E9F-C8D7-4D59-B87D-784B7D6BE0B3} - C:\Program Files\Adobe\Acrobat 7.0\ActiveX\AcroIEHelper.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\googletoolbar2.dll
O3 - Toolbar: (no name) - {EF99BD32-C1FB-11D2-892F-0090271D4F88} - (no file)
O3 - Toolbar: &Google - {2318C2B1-4965-11d4-9B18-009027A5CD4F} - c:\program files\google\googletoolbar2.dll
O4 - HKLM\..\Run: [ehTray] C:\WINDOWS\ehome\ehtray.exe
O4 - HKLM\..\Run: [MessengerPlus3] "C:\Program Files\MessengerPlus! 3\MsgPlus.exe"
O4 - HKLM\..\Run: [avast!] C:\PROGRA~1\ALWILS~1\Avast4\ashDisp.exe
O4 - HKLM\..\Run: [NeroCheck] C:\WINDOWS\system32\\NeroCheck.exe
O4 - HKCU\..\Run: [MessengerPlus3] "C:\Program Files\MessengerPlus! 3\MsgPlus.exe" /WinStart
O4 - HKCU\..\Run: [MSMSGS] "C:\Program Files\Messenger\msmsgs.exe" /background
O4 - HKCU\..\Run: [BitTorrent] "C:\Program Files\BitTorrent\bittorrent.exe" --force_start_minimized
O4 - HKCU\..\Run: [swg] C:\Program Files\Google\GoogleToolbarNotifier\1.2.1128.5462\GoogleToolbarNotifier.exe
O4 - HKCU\..\Run: [msnmsgr] "C:\Program Files\MSN Messenger\msnmsgr.exe" /background
O4 - Global Startup: Lancement rapide d'Adobe Reader.lnk = C:\Program Files\Adobe\Acrobat 7.0\Reader\reader_sl.exe
O4 - Global Startup: WinZip Quick Pick.lnk = C:\Program Files\WinZip\WZQKPICK.EXE
O8 - Extra context menu item: Add to Windows &Live Favorites - https://onedrive.live.com/?id=favorites
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
O14 - IERESET.INF: START_PAGE_URL=http://internet.sunrise.ch/fr/hom/default.asp
O16 - DPF: {6414512B-B978-451D-A0D8-FCFDF33E833C} (WUWebControl Class) - http://update.microsoft.com/windowsupdate/v6/default.aspx
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
O23 - Service: avast! iAVS4 Control Service (aswUpdSv) - Unknown owner - C:\Program Files\Alwil Software\Avast4\aswUpdSv.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: Google Updater Service (gusvc) - Google - C:\Program Files\Google\Common\Google Updater\GoogleUpdaterService.exe