Hello, I have been posting in the windoes xp section as i have had troubles with my computer restarting itself. I have done all the steps in the Read this first section, done spybot, ad aware etc.
Here is the copy of the Hijackthis-

Logfile of HijackThis v1.99.1
Scan saved at 8:50:40 AM, on 20/05/2007
Platform: Windows XP SP2 (WinNT 5.01.2600)
MSIE: Internet Explorer v7.00 (7.00.6000.16441)

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:\Program Files\Windows Defender\MsMpEng.exe
C:\WINDOWS\System32\svchost.exe
C:\Program Files\Ahead\InCD\InCDsrv.exe
C:\WINDOWS\system32\spoolsv.exe
C:\WINDOWS\Explorer.EXE
C:\PROGRA~1\Grisoft\AVGFRE~1\avgamsvr.exe
C:\Program Files\Windows Defender\MSASCui.exe
C:\PROGRA~1\Grisoft\AVGFRE~1\avgupsvc.exe
C:\PROGRA~1\Grisoft\AVGFRE~1\avgcc.exe
C:\PROGRA~1\Grisoft\AVGFRE~1\avgemc.exe
C:\Program Files\QuickTime\qttask.exe
C:\Program Files\Java\jre1.6.0_01\bin\jusched.exe
C:\WINDOWS\system32\ctfmon.exe
C:\Program Files\Common Files\Microsoft Shared\VS7Debug\mdm.exe
C:\WINDOWS\system32\ScsiAccess.EXE
C:\WINDOWS\System32\PAStiSvc.exe
C:\WINDOWS\System32\svchost.exe
C:\Program Files\Common Files\Microsoft Shared\Works Shared\WkCalRem.exe
C:\Program Files\Outlook Express\msimn.exe
C:\Program Files\Mozilla Firefox\firefox.exe
C:\Program Files\HijackThis\HijackThis.exe

R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Search Bar = http://g.ninemsn.com.au/0SEENAU/SAOS01?FORM=TOOLBR
R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Search Page = http://g.ninemsn.com.au/0SEENAU/SAOS01?FORM=TOOLBR
R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Start Page = http://news.bbc.co.uk/sport2/hi/foot...er/default.stm
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Default_Page_URL = http://go.microsoft.com/fwlink/?LinkId=69157
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Default_Search_URL = http://go.microsoft.com/fwlink/?LinkId=54896
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Search Page = http://go.microsoft.com/fwlink/?LinkId=54896
R0 - HKLM\Software\Microsoft\Internet Explorer\Main,Start Page = http://go.microsoft.com/fwlink/?LinkId=69157
R1 - HKCU\Software\Microsoft\Internet Explorer\SearchURL,(Default) = http://g.ninemsn.com.au/0SEENAU/SAOS01?FORM=TOOLBR
O2 - BHO: Adobe PDF Reader Link Helper - {06849E9F-C8D7-4D59-B87D-784B7D6BE0B3} - C:\Program Files\Adobe\Acrobat 7.0\ActiveX\AcroIEHelper.dll
O2 - BHO: Skype add-on (mastermind) - {22BF413B-C6D2-4d91-82A9-A0F997BA588C} - C:\Program Files\Skype\Toolbars\Internet Explorer\SkypeIEPlugin.dll
O2 - BHO: (no name) - {53707962-6F74-2D53-2644-206D7942484F} - C:\PROGRA~1\SPYBOT~1\SDHelper.dll
O2 - BHO: SSVHelper Class - {761497BB-D6F0-462C-B6EB-D4DAF1D92D43} - C:\Program Files\Java\jre1.6.0_01\bin\ssv.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\Common Files\Microsoft Shared\Windows Live\WindowsLiveLogin.dll
O2 - BHO: Google Toolbar Helper - {AA58ED58-01DD-4d91-8333-CF10577473F7} - c:\program files\google\googletoolbar4.dll
O3 - Toolbar: &Google - {2318C2B1-4965-11d4-9B18-009027A5CD4F} - c:\program files\google\googletoolbar4.dll
O4 - HKLM\..\Run: [Windows Defender] "C:\Program Files\Windows Defender\MSASCui.exe" -hide
O4 - HKLM\..\Run: [AVG7_CC] C:\PROGRA~1\Grisoft\AVGFRE~1\avgcc.exe /STARTUP
O4 - HKLM\..\Run: [QuickTime Task] "C:\Program Files\QuickTime\qttask.exe" -atboottime
O4 - HKLM\..\Run: [SunJavaUpdateSched] "C:\Program Files\Java\jre1.6.0_01\bin\jusched.exe"
O4 - HKCU\..\Run: [ctfmon.exe] C:\WINDOWS\system32\ctfmon.exe
O4 - Startup: wkcalrem.LNK = C:\Program Files\Common Files\Microsoft Shared\Works Shared\WkCalRem.exe
O4 - Global Startup: Microsoft Office.lnk = C:\Program Files\Microsoft Office\Office10\OSA.EXE
O8 - Extra context menu item: &eBay Search - res://C:\Program Files\eBay\eBay Toolbar2\eBayTb.dll/RCSearch.html
O8 - Extra context menu item: Add to Windows &Live Favorites - http://favorites.live.com/quickadd.aspx
O9 - Extra button: (no name) - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Program Files\Java\jre1.6.0_01\bin\ssv.dll
O9 - Extra 'Tools' menuitem: Sun Java Console - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Program Files\Java\jre1.6.0_01\bin\ssv.dll
O9 - Extra button: Skype - {77BF5300-1474-4EC7-9980-D32B190E9B07} - C:\Program Files\Skype\Toolbars\Internet Explorer\SkypeIEPlugin.dll
O9 - Extra button: Run IMVU - {d9288080-1baa-4bc4-9cf8-a92d743db949} - C:\Documents and Settings\oem\Start Menu\Programs\IMVU\Run IMVU.lnk
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: 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
O11 - Options group: [INTERNATIONAL] International*
O12 - Plugin for .spop: C:\Program Files\Internet Explorer\Plugins\NPDocBox.dll
O16 - DPF: HushEncryptionEngine - https://mailserver3.hushmail.com/sha...tionEngine.cab
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: {5ED80217-570B-4DA9-BF44-BE107C0EC166} (Windows Live Safety Center Base Module) - http://cdn.scan.onecare.live.com/res...scbase8300.cab
O16 - DPF: {6414512B-B978-451D-A0D8-FCFDF33E833C} (WUWebControl Class) - http://v5.windowsupdate.microsoft.co...?1107732315841
O16 - DPF: {6E32070A-766D-4EE6-879C-DC1FA91D2FC3} (MUWebControl Class) - http://update.microsoft.com/microsof...?1140043240250
O16 - DPF: {8E0D4DE5-3180-4024-A327-4DFAD1796A8D} (MessengerStatsClient Class) - http://messenger.zone.msn.com/binary...t.cab31267.cab
O16 - DPF: {B38870E4-7ECB-40DA-8C6A-595F0A5519FF} (MsnMessengerSetupDownloadControl Class) - http://messenger.msn.com/download/Ms...Downloader.cab
O16 - DPF: {D27CDB6E-AE6D-11CF-96B8-444553540000} (Shockwave Flash Object) - http://fpdownload2.macromedia.com/ge...sh/swflash.cab
O16 - DPF: {F58E1CEF-A068-4C15-BA5E-587CAF3EE8C6} (MSN Chat Control 4.5) - http://fdl.msn.com/public/chat/msnchat45.cab
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
O18 - Protocol: skype4com - {FFC8B962-9B40-4DFF-9458-1830C7DD7F5D} - C:\PROGRA~1\COMMON~1\Skype\SKYPE4~1.DLL
O20 - Winlogon Notify: avldr - C:\WINDOWS\
O20 - Winlogon Notify: WgaLogon - C:\WINDOWS\SYSTEM32\WgaLogon.dll
O21 - SSODL: WPDShServiceObj - {AAA288BA-9A4C-45B0-95D7-94D524869DB5} - C:\WINDOWS\system32\WPDShServiceObj.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: AVG E-mail Scanner (AVGEMS) - GRISOFT, s.r.o. - C:\PROGRA~1\Grisoft\AVGFRE~1\avgemc.exe
O23 - Service: Google Updater Service (gusvc) - Google - C:\Program Files\Google\Common\Google Updater\GoogleUpdaterService.exe
O23 - Service: InCD Helper (InCDsrv) - Nero AG - C:\Program Files\Ahead\InCD\InCDsrv.exe
O23 - Service: Pml Driver HPZ12 - HP - C:\WINDOWS\system32\HPZipm12.exe
O23 - Service: ScsiAccess - Unknown owner - C:\WINDOWS\system32\ScsiAccess.EXE
O23 - Service: STI Simulator - Unknown owner - C:\WINDOWS\System32\PAStiSvc.exe

Thanks so much for all your help. I hope i can sort it out without having to reformat my computer.

I do not see any issues in your HijackThis LOG.

Your issues are more likely hardware related (bad memory, failing power supply, failing video card, etc) or overheating related (poor cooling, failing fans, etc.) after intense processing activity or passage of time.

Thanks for looking and replying,
Bum...I guess its just and old computer ready to die . Time to buy a new one hey.
Thanks for all your help.