Virus : des fenêtres qui s'ouvrent

Bonjour,

J'ai moi aussi des fenêtres qui s'ouvrent sans cesse pour télécharger des faux antivirus.
Je n'ai pas envie pour le moment de tout formater. Je souhaiterais donc faire intervenir les anti-spyware, etc.

Voici le rapport hijackthis :

Logfile of HijackThis v1.99.1
Scan saved at 21:50:16, on 13/10/2006
Platform: Windows XP SP2 (WinNT 5.01.2600)
MSIE: Internet Explorer v6.00 SP2 (6.00.2900.2180)

Running processes:
H:\WINDOWS\System32\smss.exe
H:\WINDOWS\system32\winlogon.exe
H:\WINDOWS\system32\services.exe
H:\WINDOWS\system32\lsass.exe
H:\WINDOWS\system32\svchost.exe
H:\WINDOWS\System32\svchost.exe
H:\WINDOWS\system32\spoolsv.exe
H:\Program Files\Alwil Software\Avast4\aswUpdSv.exe
H:\WINDOWS\system32\Ati2evxx.exe
H:\Program Files\Alwil Software\Avast4\ashServ.exe
H:\Program Files\Alcohol Soft\Alcohol 120\StarWind\StarWindService.exe
H:\WINDOWS\system32\svchost.exe
H:\WINDOWS\Explorer.EXE
H:\Program Files\Alwil Software\Avast4\ashMaiSv.exe
H:\Program Files\Alwil Software\Avast4\ashWebSv.exe
H:\Program Files\TortoiseSVN\bin\TSVNCache.exe
H:\Program Files\ATI Technologies\ATI Control Panel\atiptaxx.exe
H:\Program Files\Java\jre1.5.0_06\bin\jusched.exe
H:\PROGRA~1\ALWILS~1\Avast4\ashDisp.exe
H:\Program Files\Grisoft\AVG Anti-Spyware 7.5\avgas.exe
H:\WINDOWS\system32\ctfmon.exe
H:\Program Files\Messenger\msmsgs.exe
H:\Program Files\MSN Messenger\MsnMsgr.Exe
H:\Program Files\SystemControl\SystemControl\SystemControl.exe
H:\WINDOWS\system32\wscntfy.exe
H:\Program Files\Mozilla Firefox\firefox.exe
H:\Documents and Settings\Giulietta\Bureau\HijackThis.exe

R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Start Page = https://www.google.fr/?gws_rd=ssl
R0 - HKCU\Software\Microsoft\Internet Explorer\Toolbar,LinksFolderName =
O3 - Toolbar: Alcohol Soft - Alcohol 120% Toolbar - {1CE4EE89-2D5C-4361-AF3B-D902AB545381} - H:\Program Files\Alcohol Soft\Alcohol 120% Toolbar\a120_tb.dll (file missing)
O3 - Toolbar: Yahoo! Toolbar - {EF99BD32-C1FB-11D2-892F-0090271D4F88} - H:\Program Files\Yahoo!\Companion\Installs\cpn\yt.dll
O4 - HKLM\..\Run: [Cmaudio] RunDll32 cmicnfg.cpl,CMICtrlWnd
O4 - HKLM\..\Run: [ATIPTA] "H:\Program Files\ATI Technologies\ATI Control Panel\atiptaxx.exe"
O4 - HKLM\..\Run: [SunJavaUpdateSched] "H:\Program Files\Java\jre1.5.0_06\bin\jusched.exe"
O4 - HKLM\..\Run: [avast!] H:\PROGRA~1\ALWILS~1\Avast4\ashDisp.exe
O4 - HKLM\..\Run: [MSConfig] H:\WINDOWS\PCHealth\HelpCtr\Binaries\MSConfig.exe /auto
O4 - HKCU\..\Run: [CTFMON.EXE] H:\WINDOWS\system32\ctfmon.exe
O4 - Global Startup: Adobe Gamma Loader.lnk = H:\Program Files\Fichiers communs\Adobe\Calibration\Adobe Gamma Loader.exe
O4 - Global Startup: Lancement rapide d'Adobe Reader.lnk = H:\Program Files\Adobe\Acrobat 7.0\Reader\reader_sl.exe
O4 - Global Startup: Microsoft Office.lnk = H:\Program Files\Microsoft Office\Office10\OSA.EXE
O4 - Global Startup: SystemControl.lnk = ?
O8 - Extra context menu item: Add to AMV Convert Tool... - H:\Program Files\MP3 Player Utilities 3.73\AMVConverter\grab.html
O8 - Extra context menu item: E&xporter vers Microsoft Excel - res://H:\PROGRA~1\MICROS~2\Office10\EXCEL.EXE/3000
O8 - Extra context menu item: MediaManager tool grab multimedia file - H:\Program Files\MP3 Player Utilities 3.73\MediaManager\grab.html
O9 - Extra button: (no name) - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - H:\Program Files\Java\jre1.5.0_06\bin\ssv.dll
O9 - Extra 'Tools' menuitem: Console Java (Sun) - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - H:\Program Files\Java\jre1.5.0_06\bin\ssv.dll
O9 - Extra button: Messenger - {FB5F1910-F110-11d2-BB9E-00C04F795683} - H:\Program Files\Messenger\msmsgs.exe
O9 - Extra 'Tools' menuitem: Windows Messenger - {FB5F1910-F110-11d2-BB9E-00C04F795683} - H:\Program Files\Messenger\msmsgs.exe
O16 - DPF: {A13516A3-BE86-4517-813C-B5FF0C8ACDF3} (Toontown Installer ActiveX Control French) - http://downloadtoontown.goa.com/sv1.5.14.5/ttinst-french.cab
O18 - Protocol: livecall - {828030A1-22C1-4009-854F-8E305202313F} - H:\PROGRA~1\MSNMES~1\MSGRAP~1.DLL
O18 - Protocol: msnim - {828030A1-22C1-4009-854F-8E305202313F} - H:\PROGRA~1\MSNMES~1\MSGRAP~1.DLL
O21 - SSODL: WPDShServiceObj - {AAA288BA-9A4C-45B0-95D7-94D524869DB5} - H:\WINDOWS\system32\WPDShServiceObj.dll
O23 - Service: avast! iAVS4 Control Service (aswUpdSv) - Unknown owner - H:\Program Files\Alwil Software\Avast4\aswUpdSv.exe
O23 - Service: Ati HotKey Poller - Unknown owner - H:\WINDOWS\system32\Ati2evxx.exe
O23 - Service: ATI Smart - Unknown owner - H:\WINDOWS\system32\ati2sgag.exe
O23 - Service: avast! Antivirus - Unknown owner - H:\Program Files\Alwil Software\Avast4\ashServ.exe
O23 - Service: avast! Mail Scanner - Unknown owner - H:\Program Files\Alwil Software\Avast4\ashMaiSv.exe" /service (file missing)
O23 - Service: avast! Web Scanner - Unknown owner - H:\Program Files\Alwil Software\Avast4\ashWebSv.exe" /service (file missing)
O23 - Service: AVG Anti-Spyware Guard - Anti-Malware Development a.s. - H:\Program Files\Grisoft\AVG Anti-Spyware 7.5\guard.exe
O23 - Service: InstallDriver Table Manager (IDriverT) - Macrovision Corporation - H:\Program Files\Fichiers communs\InstallShield\Driver\11\Intel 32\IDriverT.exe
O23 - Service: LiveUpdate - Unknown owner - H:\PROGRA~1\Symantec\LIVEUP~1\LUCOMS~1.EXE (file missing)
O23 - Service: Macromedia Licensing Service - Unknown owner - H:\Program Files\Fichiers communs\Macromedia Shared\Service\Macromedia Licensing.exe
O23 - Service: StarWind iSCSI Service (StarWindService) - Rocket Division Software - H:\Program Files\Alcohol Soft\Alcohol 120\StarWind\StarWindService.exe

Que dois-je faire ensuite ?

Je vous remercie pour votre aide précieuse,