ouverture automatique de explorer.exe au démarrage windows2000

merci de me tuyauter:à l'ouverture de ma session windows2000 la fenêtre explorer s'ouvre systématiquement sur "Mickey" mon nom d'utilisateur dans "documents et settings".
A l'inverse , quand je veux arreter mon PC , celui ci reste bloqué sur un fond d'écran avec le curseur de la souris également bloqué.J'ai cherché sur le net mais n'ai pas encore trouvé la solution .Merci pour votre aide
j'ai fait un Hijackthis et voici le résultat à tout hasard:Logfile of HijackThis v1.99.1
Scan saved at 8:55:22, on 10/04/2006
Platform: Windows 2000 (WinNT 5.00.2195)
MSIE: Internet Explorer v5.00 (5.00.2920.0000)

Running processes:
C:\WINNT\System32\smss.exe
C:\WINNT\system32\winlogon.exe
C:\WINNT\system32\services.exe
C:\WINNT\system32\lsass.exe
C:\WINNT\system32\svchost.exe
C:\WINNT\system32\spoolsv.exe
C:\Program Files\Alwil Software\Avast4\aswUpdSv.exe
C:\Program Files\Alwil Software\Avast4\ashServ.exe
C:\WINNT\System32\svchost.exe
C:\WINNT\system32\hidserv.exe
C:\WINNT\system32\regsvc.exe
C:\WINNT\system32\MSTask.exe
C:\WINNT\system32\svchost.exe
C:\WINNT\System32\msdtc.exe
C:\Program Files\Alwil Software\Avast4\ashWebSv.exe
C:\Program Files\Alwil Software\Avast4\ashMaiSv.exe
C:\WINNT\system32\msiexec.exe
C:\WINNT\Explorer.exe
C:\WINNT\System32\atiptaxx.exe
C:\PROGRA~1\ALWILS~1\Avast4\ashDisp.exe
C:\WINNT\System32\RunDll32.exe
C:\Program Files\MessengerPlus! 3\MsgPlus.exe
C:\Program Files\QuickTime\qttask.exe
C:\Program Files\iTunes\iTunesHelper.exe
C:\Program Files\iPod\bin\iPodService.exe
C:\Program Files\ahead\InCD\InCD.exe
C:\WINNT\System32\internat.exe
C:\Program Files\Internet Explorer\IEXPLORE.EXE
C:\Documents and Settings\mickey\Local Settings\Temporary Internet Files\Content.IE5\WEQLAA7V\HijackThis[1].exe

R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Start Page = http://www.7sur7.be/
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Default_Page_URL = http://www.fr.msn.com
R0 - HKCU\Software\Microsoft\Internet Explorer\Toolbar,LinksFolderName = Liens
O2 - BHO: Yahoo! Companion BHO - {02478D38-C3F9-4efb-9B51-7695ECA05670} - C:\PROGRA~1\YAHOO!\COMPAN~1\INSTALLS\cpn0\ycomp5_6_2_0.dll
O2 - BHO: Adobe PDF Reader Link Helper - {06849E9F-C8D7-4D59-B87D-784B7D6BE0B3} - C:\Program Files\Adobe\Acrobat 7.0\ActiveX\AcroIEHelper.dll
O2 - BHO: EoRezoBHO - {64F56FC1-1272-44CD-BA6E-39723696E350} - (no file)
O2 - BHO: SSVHelper Class - {761497BB-D6F0-462C-B6EB-D4DAF1D92D43} - C:\Program Files\Java\jre1.5.0_06\bin\ssv.dll
O2 - BHO: Google Toolbar Helper - {AA58ED58-01DD-4d91-8333-CF10577473F7} - c:\program files\google\googletoolbar2.dll
O3 - Toolbar: Yahoo! Barre d'outils - {EF99BD32-C1FB-11D2-892F-0090271D4F88} - C:\PROGRA~1\YAHOO!\COMPAN~1\INSTALLS\cpn0\ycomp5_6_2_0.dll
O3 - Toolbar: &Google - {2318C2B1-4965-11d4-9B18-009027A5CD4F} - c:\program files\google\googletoolbar2.dll
O3 - Toolbar: ToolbarDesigner - {5b084ff8-5ce4-43dd-9319-55fbb4dddea3} - C:\Program Files\CrackSearch\toolbar.dll
O3 - Toolbar: @msdxmLC.dll,-1@1036,&Radio - {8E718888-423F-11D2-876E-00A0C9082467} - C:\WINNT\System32\msdxm.ocx
O4 - HKLM\..\Run: [Synchronization Manager] mobsync.exe /logon
O4 - HKLM\..\Run: [AtiPTA] atiptaxx.exe
O4 - HKLM\..\Run: [avast!] C:\PROGRA~1\ALWILS~1\Avast4\ashDisp.exe
O4 - HKLM\..\Run: [SunJavaUpdateSched] C:\Program Files\Java\jre1.5.0_06\bin\jusched.exe
O4 - HKLM\..\Run: [gcasServ] "C:\Program Files\Microsoft AntiSpyware\gcasServ.exe"
O4 - HKLM\..\Run: [SoundFusion] RunDll32 hercplgs.cpl,BootEntryPoint
O4 - HKLM\..\Run: [HGTXPEI] C:\WINNT\system32\FirstReboot.exe
O4 - HKLM\..\Run: [MessengerPlus3] "C:\Program Files\MessengerPlus! 3\MsgPlus.exe"
O4 - HKLM\..\Run: [QuickTime Task] "C:\Program Files\QuickTime\qttask.exe" -atboottime
O4 - HKLM\..\Run: [iTunesHelper] "C:\Program Files\iTunes\iTunesHelper.exe"
O4 - HKLM\..\Run: [CloneCDElbyCDFL] "C:\Program Files\Elaborate Bytes\CloneCD\ElbyCheck.exe" /L ElbyCDFL
O4 - HKLM\..\Run: [InCD] C:\Program Files\ahead\InCD\InCD.exe
O4 - HKLM\..\Run: [NeroFilterCheck] C:\WINNT\system32\NeroCheck.exe
O4 - HKLM\..\Run: [LoadQM] loadqm.exe
O4 - HKCU\..\Run: [lycosInside] C:\Program Files\lycos\Lyc_SysTray.exe
O4 - HKCU\..\Run: [SystemCheck] RUNDLL32.EXE syschecks.dll,SysCheckStartup
O4 - HKCU\..\Run: [internat.exe] internat.exe
O4 - Global Startup: Lancement rapide d'Adobe Reader.lnk = C:\Program Files\Adobe\Acrobat 7.0\Reader\reader_sl.exe
O8 - Extra context menu item: &Traduire à partir de l'anglais - res://c:\program files\google\GoogleToolbar2.dll/cmwordtrans.html
O8 - Extra context menu item: Pages liées - res://c:\program files\google\GoogleToolbar2.dll/cmbacklinks.html
O8 - Extra context menu item: Pages similaires - res://c:\program files\google\GoogleToolbar2.dll/cmsimilar.html
O8 - Extra context menu item: Recherche &Google - res://c:\program files\google\GoogleToolbar2.dll/cmsearch.html
O8 - Extra context menu item: Version de la page actuelle disponible dans le cache Google - res://c:\program files\google\GoogleToolbar2.dll/cmcache.html
O9 - Extra button: (no name) - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Program Files\Java\jre1.5.0_06\bin\ssv.dll
O9 - Extra 'Tools' menuitem: Console Java (Sun) - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Program Files\Java\jre1.5.0_06\bin\ssv.dll
O9 - Extra button: Related - {c95fe080-8f5d-11d2-a20b-00aa003c157a} - C:\WINNT\web\related.htm
O9 - Extra 'Tools' menuitem: Show &Related Links - {c95fe080-8f5d-11d2-a20b-00aa003c157a} - C:\WINNT\web\related.htm
O12 - Plugin for .mu3: C:\Program Files\Internet Explorer\Plugins\NPMyrMus.dll
O12 - Plugin for .mus: C:\Program Files\Internet Explorer\Plugins\NPMyrMus.dll
O12 - Plugin for .mut: C:\Program Files\Internet Explorer\Plugins\NPMyrMus.dll
O12 - Plugin for .myr: C:\Program Files\Internet Explorer\Plugins\NPMyrMus.dll
O12 - Plugin for .wcs: C:\Program Files\Internet Explorer\PLUGINS\nppdf32.dll
O14 - IERESET.INF: START_PAGE_URL=http://www.fr.msn.com
O14 - IERESET.INF: MS_START_PAGE_URL=http://www.fr.msn.com
O16 - DPF: {1239CC52-59EF-4DFA-8C61-90FFA846DF7E} (Musicnotes Viewer) - http://www.musicnotes.com/download/mnviewer.cab
O16 - DPF: {15589FA1-C456-11CE-BF01-00AA0055595A} - http://w4s.work4sure.com/c/ge/w4sgeen9.exe
O16 - DPF: {17492023-C23A-453E-A040-C7C580BBF700} (Windows Genuine Advantage Validation Tool) - http://go.microsoft.com/fwlink/?linkid=39204
O16 - DPF: {4F1E5B1A-2A80-42CA-8532-2D05CB959537} (MSN Photo Upload Tool) - http://spaces.msn.com//PhotoUpload/MsnPUpld.cab
O16 - DPF: {5CE7A7AF-8C5E-48CF-AE30-8FC6F01C27E3} (Yahoo! Photos - Outil de publication Class) - http://us.dl1.yimg.com/download.ya [...] r1_6fr.cab
O16 - DPF: {62789780-B744-11D0-986B-00609731A21D} (Autodesk MapGuide ActiveX Control) - http://www.mapsonline.be/Install/mgaxctrl.cab
O16 - DPF: {9059F30F-4EB1-4BD2-9FDC-36F43A218F4A} (Microsoft RDP Client Control (redist)) - http://www.altair.be/TSWeb/msrdp.cab
O16 - DPF: {90C9629E-CD32-11D3-BBFB-00105A1F0D68} (InstallShield International Setup Player) - http://www.lizardtech.com/download [...] isetup.cab
O16 - DPF: {A8F2B9BD-A6A0-486A-9744-18920D898429} (ScorchPlugin Class) - http://www.sibelius.com/download/s [...] Plugin.cab
O16 - DPF: {B38870E4-7ECB-40DA-8C6A-595F0A5519FF} (MsnMessengerSetupDownloadControl Class) - http://messenger.msn.com/download/ [...] loader.cab
O16 - DPF: {C36112BF-2FA3-4694-8603-3B510EA3B465} (Lycos File Upload Component) - http://f004.mail.caramail.lycos.fr [...] loader.cab
O16 - DPF: {EB387D2F-E27B-4D36-979E-847D1036C65D} (QDiagHUpdateObj Class) - http://h30043.www3.hp.com/hpdj/fr/check/qdiagh.cab?326
O16 - DPF: {FD0B6769-6490-4A91-AA0A-B5AE0DC75AC9} (Performance Viewer Activex Control) - https://secure.logmein.com/activex/ractrl.cab
O18 - Filter: text/html - {2AB289AE-4B90-4281-B2AE-1F4BB034B647} - (no file)
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: Service d'administration du Gestionnaire de disque logique (dmadmin) - VERITAS Software Corp. - C:\WINNT\System32\dmadmin.exe
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: PDEngine - Raxco Software, Inc. - C:\Program Files\Raxco\PerfectDisk\PDEngine.exe
O23 - Service: PDScheduler (PDSched) - Raxco Software, Inc. - C:\Program Files\Raxco\PerfectDisk\PDSched.exe