Desktop bloccato

[mimmo1978]

navigando su internet devo aver beccato qualcosa che mi ha fatto riavviare il sistema. Al riavvio lo sfondo del desktop era di colore blu. Dopo aver ripulito con pctools doctor spyware e avg free è tornata l'immagine di prima , ma se vado per cambiarla da proprietà schermo- desktop - i nomi delle immagini non son selezionabili. Posso solo clikkare su personalizza desktop per cambiare il colore di sfondo.
Cosa è successo?
devo formattare ?
ciao grazie ant. per l'aiuto
se puo essere utile questo e il file log di hijackthis
Logfile of HijackThis v1.99.1
Scan saved at 20.10.13, on 29/09/2006
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\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:\WINDOWS\Explorer.EXE
C:\PROGRA~1\Grisoft\AVGFRE~1\avgamsvr.exe
C:\PROGRA~1\Grisoft\AVGFRE~1\avgupsvc.exe
C:\Programmi\File comuni\LightScribe\LSSrvc.exe
C:\WINDOWS\system32\nvsvc32.exe
C:\Programmi\Spyware Doctor\sdhelp.exe
C:\WINDOWS\System32\svchost.exe
C:\PROGRA~1\Grisoft\AVGFRE~1\avgcc.exe
C:\PROGRA~1\Grisoft\AVGFRE~1\avgemc.exe
C:\WINDOWS\system32\rundll32.exe
C:\WINDOWS\system32\ctfmon.exe
C:\Programmi\Spyware Doctor\swdoctor.exe
C:\Programmi\Messenger\msmsgs.exe
C:\WINDOWS\system32\NotifyPhoneBook.exe
C:\WINDOWS\System32\alg.exe
C:\Programmi\Internet Explorer\iexplore.exe
C:\Programmi\WinRAR\WinRAR.exe
C:\DOCUME~1\mimmo\IMPOST~1\Temp\Rar$EX00.469\HijackThis.exe

R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Start Page = http://www.google.it/
R1 - HKCU\Software\Microsoft\Internet Connection Wizard,ShellNext = http://www.lavasoft.de/ad-aware/per...6/upgrade.shtml
R0 - HKCU\Software\Microsoft\Internet Explorer\Toolbar,LinksFolderName = Collegamenti
O2 - BHO: Adobe PDF Reader Link Helper - {06849E9F-C8D7-4D59-B87D-784B7D6BE0B3} - C:\Programmi\Adobe\Acrobat 7.0\ActiveX\AcroIEHelper.dll
O2 - BHO: (no name) - {53707962-6F74-2D53-2644-206D7942484F} - C:\Programmi\Spybot - Search & Destroy\SDHelper.dll
O2 - BHO: PCTools Site Guard - {5C8B2A36-3DB1-42A4-A3CB-D426709BBFEB} - C:\PROGRA~1\SPYWAR~1\tools\iesdsg.dll
O2 - BHO: Google Toolbar Helper - {AA58ED58-01DD-4d91-8333-CF10577473F7} - c:\programmi\google\googletoolbar2.dll
O2 - BHO: PCTools Browser Monitor - {B56A7D7D-6927-48C8-A975-17DF180C71AC} - C:\PROGRA~1\SPYWAR~1\tools\iesdpb.dll
O3 - Toolbar: &Google - {2318C2B1-4965-11d4-9B18-009027A5CD4F} - c:\programmi\google\googletoolbar2.dll
O4 - HKLM\..\Run: [AVG7_CC] C:\PROGRA~1\Grisoft\AVGFRE~1\avgcc.exe /STARTUP
O4 - HKLM\..\Run: [AVG7_EMC] C:\PROGRA~1\Grisoft\AVGFRE~1\avgemc.exe
O4 - HKLM\..\Run: [AME_CSA] rundll32 amecsa.cpl,RUN_DLL
O4 - HKLM\..\Run: [NeroFilterCheck] C:\WINDOWS\system32\NeroCheck.exe
O4 - HKLM\..\Run: [MSConfig] C:\WINDOWS\PCHealth\HelpCtr\Binaries\MSConfig.exe /auto
O4 - HKCU\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\ctfmon.exe
O4 - HKCU\..\Run: [Spyware Doctor] "C:\Programmi\Spyware Doctor\swdoctor.exe" /Q
O4 - HKCU\..\Run: [MSMSGS] "C:\Programmi\Messenger\msmsgs.exe" /background
O8 - Extra context menu item: E&sporta in Microsoft Excel - res://C:\PROGRA~1\MICROS~2\OFFICE11\EXCEL.EXE/3000
O9 - Extra button: Spyware Doctor - {2D663D1A-8670-49D9-A1A5-4C56B4E14E84} - C:\PROGRA~1\SPYWAR~1\tools\iesdpb.dll
O9 - Extra button: Ricerche - {92780B25-18CC-41C8-B9BE-3C9C571A8263} - C:\PROGRA~1\MICROS~2\OFFICE11\REFIEBAR.DLL
O9 - Extra button: Messenger - {FB5F1910-F110-11d2-BB9E-00C04F795683} - C:\Programmi\Messenger\msmsgs.exe
O9 - Extra 'Tools' menuitem: Windows Messenger - {FB5F1910-F110-11d2-BB9E-00C04F795683} - C:\Programmi\Messenger\msmsgs.exe
O15 - Trusted Zone: www.archivio.name
O16 - DPF: {9A9307A0-7DA4-4DAF-B042-5009F29E09E1} (ActiveScan Installer Class) - http://acs.pandasoftware.com/active...free/asinst.cab
O17 - HKLM\System\CCS\Services\Tcpip\..\{B8EB21D7-7D47-4606-B200-9BBBD841F6A7}: NameServer = 85.37.17.51 85.38.28.97
O18 - Protocol: ms-help - {314111C7-A502-11D2-BBCA-00C04F8EC294} - C:\Programmi\File comuni\Microsoft Shared\Help\hxds.dll
O23 - Service: AVG7 Alert Manager Server (Avg7Alrt) - GRISOFT, s.r.o. - C:\PROGRA~1\Grisoft\AVGFRE~1\avgamsvr.exe
O23 - Service: AVG7 Update Service (Avg7UpdSvc) - GRISOFT, s.r.o. - C:\PROGRA~1\Grisoft\AVGFRE~1\avgupsvc.exe
O23 - Service: LightScribeService Direct Disc Labeling Service (LightScribeService) - Hewlett-Packard Company - C:\Programmi\File comuni\LightScribe\LSSrvc.exe
O23 - Service: NVIDIA Driver Helper Service (NVSvc) - NVIDIA Corporation - C:\WINDOWS\system32\nvsvc32.exe
O23 - Service: PC Tools Spyware Doctor (SDhelper) - PC Tools Research Pty Ltd - C:\Programmi\Spyware Doctor\sdhelp.exe