Mon probleme: que faire avec hijackthis

Bonjour,
J ai un pc avec Windows xp familliale et j'ai des problemes a plusieurs niveaux:
- un message de fermeture " Winlogon.exe a rencontrer un probléme et doit etre fermé..."
- des problemes de navigations sur internet
- une erreur lorsque j'arrete ou je redemarre le pc: ecran bleu avec ecrit " STOP: c000021{erreur systeme... "

Apres avoir recherché sur le net, j'ai pu voir que il fallait que je traite le probleme avec hijackthis mais je ne sais comment faire aprés...

Pourriez vous m'aider ....
Mon Scan me donne:

Logfile of HijackThis v1.99.1
Scan saved at 19:01:41, on 06/12/2006
Platform: Windows XP SP2 (WinNT 5.01.2600)
MSIE: Internet Explorer v7.00 (7.00.5730.0011)

Running processes:
C:\WINDOWS\System32\smss.exe
C:\WINDOWS\system32\csrss.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\svchost.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:\Program Files\Grisoft\AVG Anti-Spyware 7.5\guard.exe
C:\WINDOWS\system32\drivers\CDAC11BA.EXE
C:\Program Files\Alcohol Soft\Alcohol 120\StarWind\StarWindService.exe
C:\WINDOWS\system32\svchost.exe
C:\WINDOWS\system32\wdfmgr.exe
C:\WINDOWS\System32\alg.exe
C:\WINDOWS\Explorer.EXE
C:\WINDOWS\system32\hkcmd.exe
C:\WINDOWS\system32\igfxpers.exe
C:\Program Files\Synaptics\SynTP\SynTPEnh.exe
C:\WINDOWS\SOUNDMAN.EXE
C:\WINDOWS\VM_STI.EXE
C:\Program Files\QuickTime\qttask.exe
C:\PROGRA~1\NUMERI~1\MONASS~1\SMARTB~1\MotiveSB.exe
C:\PROGRA~1\ALWILS~1\Avast4\ashDisp.exe
C:\Program Files\Grisoft\AVG Anti-Spyware 7.5\avgas.exe
C:\WINDOWS\system32\ctfmon.exe
C:\Program Files\MSN Messenger\MsnMsgr.Exe
C:\Program Files\Logitech\Desktop Messenger\8876480\Program\LogitechDesktopMessenger.exe
C:\Program Files\Logitech\SetPoint\SetPoint.exe
C:\Program Files\Fichiers communs\Logitech\KHAL\KHALMNPR.EXE
c:\Program Files\Numericable\Mon Assistant Internet\bin\mad.exe
c:\Program Files\Numericable\Mon Assistant Internet\bin\mpbtn.exe
C:\PROGRA~1\Motive\ASSTCO~1\MOTIVE~1.EXE
C:\Program Files\Alwil Software\Avast4\ashMaiSv.exe
C:\Program Files\Alwil Software\Avast4\ashWebSv.exe
C:\WINDOWS\system32\igfxsrvc.exe
C:\Program Files\Google\GoogleToolbarNotifier\1.2.908.5008\GoogleToolbarNotifier.exe
C:\Program Files\Mozilla Firefox\firefox.exe
C:\Program Files\WinRAR\WinRAR.exe
C:\DOCUME~1\Steven\LOCALS~1\Temp\Rar$EX03.078\HijackThis.exe

R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Start Page = https://www.google.fr/?gws_rd=ssl
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Default_Page_URL = https://www.msn.com/fr-fr/?ocid=iehp
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Default_Search_URL = https://www.bing.com/?toHttps=1&redig=5FC791212101479BAFBE1A679848B1AF
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Search Page = https://www.bing.com/?toHttps=1&redig=5FC791212101479BAFBE1A679848B1AF
R0 - HKLM\Software\Microsoft\Internet Explorer\Main,Start Page = https://www.msn.com/fr-fr/?ocid=iehp
R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Window Title = Internet Explorer par NUMERICABLE
R1 - HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings,ProxyOverride = 127.0.0.1
R0 - HKCU\Software\Microsoft\Internet Explorer\Toolbar,LinksFolderName = Liens
O2 - BHO: Seekmo Search Assistant Helper /fleok=1D8A83A5C2E6137B9AA575760EA83FA5EF80752B94E2DE7F5974442137C2 - {5929CD6E-2062-44a4-B2C5-2C7E78FBAB38} - c:\program files\seekmo\seekmohook.dll (file missing)
O2 - BHO: Google Toolbar Helper - {AA58ED58-01DD-4d91-8333-CF10577473F7} - c:\program files\google\googletoolbar2.dll
O3 - Toolbar: &Google - {2318C2B1-4965-11d4-9B18-009027A5CD4F} - c:\program files\google\googletoolbar2.dll
O3 - Toolbar: PDFCreator Toolbar - {31CF9EBE-5755-4A1D-AC25-2834D952D9B4} - C:\Program Files\PDFCreator Toolbar\v3.0.0.0\PDFCreator_Toolbar.dll
O4 - HKLM\..\Run: [igfxtray] C:\WINDOWS\system32\igfxtray.exe
O4 - HKLM\..\Run: [igfxhkcmd] C:\WINDOWS\system32\hkcmd.exe
O4 - HKLM\..\Run: [igfxpers] C:\WINDOWS\system32\igfxpers.exe
O4 - HKLM\..\Run: [SynTPEnh] C:\Program Files\Synaptics\SynTP\SynTPEnh.exe
O4 - HKLM\..\Run: [SoundMan] SOUNDMAN.EXE
O4 - HKLM\..\Run: [AlcWzrd] ALCWZRD.EXE
O4 - HKLM\..\Run: [Alcmtr] ALCMTR.EXE
O4 - HKLM\..\Run: [NeroFilterCheck] C:\WINDOWS\system32\NeroCheck.exe
O4 - HKLM\..\Run: [BigDogPath] C:\WINDOWS\VM_STI.EXE Philips SPC 200NC PC Camera
O4 - HKLM\..\Run: [QuickTime Task] "C:\Program Files\QuickTime\qttask.exe" -atboottime
O4 - HKLM\..\Run: [DSLAGENTEXE] dslagent.exe
O4 - HKLM\..\Run: [Workflow] D:\Workflow.exe
O4 - HKLM\..\Run: [Motive SmartBridge] C:\PROGRA~1\NUMERI~1\MONASS~1\SMARTB~1\MotiveSB.exe
O4 - HKLM\..\Run: [avast!] C:\PROGRA~1\ALWILS~1\Avast4\ashDisp.exe
O4 - HKLM\..\Run: [Logitech Hardware Abstraction Layer] KHALMNPR.EXE
O4 - HKLM\..\Run: [!AVG Anti-Spyware] "C:\Program Files\Grisoft\AVG Anti-Spyware 7.5\avgas.exe" /minimized
O4 - HKCU\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\ctfmon.exe
O4 - HKCU\..\Run: [MsnMsgr] "C:\Program Files\MSN Messenger\MsnMsgr.Exe" /background
O4 - HKCU\..\Run: [swg] C:\Program Files\Google\GoogleToolbarNotifier\1.2.908.5008\GoogleToolbarNotifier.exe
O4 - HKCU\..\Run: [LDM] C:\Program Files\Logitech\Desktop Messenger\8876480\Program\LogitechDesktopMessenger.exe
O4 - Global Startup: Adobe Gamma Loader.lnk = C:\Program Files\Fichiers communs\Adobe\Calibration\Adobe Gamma Loader.exe
O4 - Global Startup: Lancement rapide d'Adobe Reader.lnk = C:\Program Files\Adobe\Acrobat 7.0\Reader\reader_sl.exe
O4 - Global Startup: Logitech Desktop Messenger.lnk = C:\Program Files\Logitech\Desktop Messenger\8876480\Program\LDMConf.exe
O4 - Global Startup: Logitech SetPoint.lnk = C:\Program Files\Logitech\SetPoint\SetPoint.exe
O4 - Global Startup: Mon Assistant Internet.lnk = C:\Program Files\Numericable\Mon Assistant Internet\bin\matcli.exe
O8 - Extra context menu item: E&xporter vers Microsoft Excel - res://C:\PROGRA~1\MICROS~2\OFFICE11\EXCEL.EXE/3000
O9 - Extra button: Recherche - {92780B25-18CC-41C8-B9BE-3C9C571A8263} - C:\PROGRA~1\MICROS~2\OFFICE11\REFIEBAR.DLL
O9 - Extra button: (no name) - {e2e2dd38-d088-4134-82b7-f2ba38496583} - %windir%\Network Diagnostic\xpnetdiag.exe (file missing)
O9 - Extra 'Tools' menuitem: @xpsp3res.dll,-20001 - {e2e2dd38-d088-4134-82b7-f2ba38496583} - %windir%\Network Diagnostic\xpnetdiag.exe (file missing)
O9 - Extra button: @c:\Program Files\Messenger\Msgslang.dll,-61144 - {FB5F1910-F110-11d2-BB9E-00C04F795683} - c:\Program Files\Messenger\msmsgs.exe
O9 - Extra 'Tools' menuitem: @c:\Program Files\Messenger\Msgslang.dll,-61144 - {FB5F1910-F110-11d2-BB9E-00C04F795683} - c:\Program Files\Messenger\msmsgs.exe
O11 - Options group: [INTERNATIONAL] International*
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: igfxcui - C:\WINDOWS\SYSTEM32\igfxdev.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: AVG Anti-Spyware Guard - Anti-Malware Development a.s. - C:\Program Files\Grisoft\AVG Anti-Spyware 7.5\guard.exe
O23 - Service: C-DillaCdaC11BA - Macrovision - C:\WINDOWS\system32\drivers\CDAC11BA.EXE
O23 - Service: InstallDriver Table Manager (IDriverT) - Macrovision Corporation - C:\Program Files\Fichiers communs\InstallShield\Driver\11\Intel 32\IDriverT.exe
O23 - Service: StarWind iSCSI Service (StarWindService) - Rocket Division Software - C:\Program Files\Alcohol Soft\Alcohol 120\StarWind\StarWindService.exe

Merci de m'aider.......SVP