Can anyone help?? pc keeps on restaring.

as the title says the pc keeps on restarting. now i have read about pauljc's thread regarding his problem and i dont know if my problem and his problem are similar, so i dont want to do anything unless im sure about it. ok first, i ran AVG, avas, ad -aware, and spybot search & destroy. they all just found some tracking coockies other than that its good. now every hour or every 30 mins my pc restarts itself on its own. and i dont know what the problem is. can anyone help me? -.-

oh btw. if you want the log from hijackThis here it is..

Logfile of Trend Micro HijackThis v2.0.2
Scan saved at 4:49:48 PM, on 2/20/2008
Platform: Windows XP SP1 (WinNT 5.01.2600)
MSIE: Internet Explorer v6.00 SP1 (6.00.2800.1106)
Boot mode: Normal

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:\WINDOWS\System32\svchost.exe
C:\Program Files\Lavasoft\Ad-Aware 2007\aawservice.exe
C:\WINDOWS\system32\spoolsv.exe
C:\PROGRA~1\Grisoft\AVG7\avgamsvr.exe
C:\PROGRA~1\Grisoft\AVG7\avgupsvc.exe
C:\PROGRA~1\Grisoft\AVG7\avgemc.exe
C:\Program Files\Common Files\Microsoft Shared\VS7DEBUG\MDM.EXE
C:\WINDOWS\System32\nvsvc32.exe
C:\WINDOWS\System32\svchost.exe
C:\WINDOWS\Explorer.EXE
C:\WINDOWS\RTHDCPL.EXE
C:\Program Files\D-Link\Wireless G WDA-1320\AirGCFG.exe
C:\Program Files\ANI\ANIWZCS2 Service\WZCSLDR2.exe
C:\WINDOWS\System32\RUNDLL32.EXE
C:\PROGRA~1\Grisoft\AVG7\avgcc.exe
C:\Program Files\Java\jre1.6.0_02\bin\jusched.exe
C:\Program Files\Common Files\Real\Update_OB\realsched.exe
C:\WINDOWS\FixCamera.exe
C:\Program Files\BitTorrent\bittorrent.exe
C:\Program Files\Creative\Sync Manager Unicode\CTSyncU.exe
C:\WINDOWS\System32\ctfmon.exe
C:\Program Files\Messenger\MSMSGS.EXE
C:\Program Files\WinZip\WZQKPICK.EXE
C:\PROGRA~1\Yahoo!\MESSEN~1\ymsgr_tray.exe
C:\Program Files\Internet Explorer\IEXPLORE.EXE
C:\PROGRA~1\Grisoft\AVG7\avgwb.dat
C:\Program Files\Internet Explorer\IEXPLORE.EXE
C:\Program Files\Trend Micro\HijackThis\HijackThis.exe

R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Search Bar = red.clientapps.yahoo.com/customize/ptec/...o.com/search/ie.html
R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Search Page = red.clientapps.yahoo.com/customize/ptec/...http://www.yahoo.com
R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Start Page = www.yahoo.com/
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Default_Page_URL = www.yahoo.com
R0 - HKLM\Software\Microsoft\Internet Explorer\Main,Start Page = www.yahoo.com
R1 - HKCU\Software\Microsoft\Internet Explorer\SearchURL,(Default) = red.clientapps.yahoo.com/customize/ptec/...http://www.yahoo.com
R3 - URLSearchHook: Yahoo! Toolbar - {EF99BD32-C1FB-11D2-892F-0090271D4F88} - C:\Program Files\Yahoo!\Companion\Installs\cpn0\yt.dll
F2 - REG:system.ini: UserInit=C:\WINDOWS\System32\userinit.exe,C:\WINDOWS\System32\a0234.exe,
O2 - BHO: &Yahoo! Toolbar Helper - {02478D38-C3F9-4efb-9B51-7695ECA05670} - C:\Program Files\Yahoo!\Companion\Installs\cpn0\yt.dll
O2 - BHO: Adobe PDF Reader Link Helper - {06849E9F-C8D7-4D59-B87D-784B7D6BE0B3} - C:\Program Files\Common Files\Adobe\Acrobat\ActiveX\AcroIEHelper.dll
O2 - BHO: (no name) - {53707962-6F74-2D53-2644-206D7942484F} - C:\PROGRA~1\SPYBOT~1\SDHelper.dll
O2 - BHO: Yahoo! IE Services Button - {5BAB4B5B-68BC-4B02-94D6-2FC0DE4A7897} - C:\Program Files\Yahoo!\Common\yiesrvc.dll
O2 - BHO: SSVHelper Class - {761497BB-D6F0-462C-B6EB-D4DAF1D92D43} - C:\Program Files\Java\jre1.6.0_02\bin\ssv.dll
O2 - BHO: Flash Module - {87C0BA52-F363-4419-8AC1-D7270A668687} - ktask.dll (file missing)
O3 - Toolbar: Yahoo! Toolbar - {EF99BD32-C1FB-11D2-892F-0090271D4F88} - C:\Program Files\Yahoo!\Companion\Installs\cpn0\yt.dll
O3 - Toolbar: &Radio - {8E718888-423F-11D2-876E-00A0C9082467} - C:\WINDOWS\System32\msdxm.ocx
O4 - HKLM\..\Run: [RTHDCPL] RTHDCPL.EXE
O4 - HKLM\..\Run: [SkyTel] SkyTel.EXE
O4 - HKLM\..\Run: [Alcmtr] ALCMTR.EXE
O4 - HKLM\..\Run: [D-Link Wireless G WDA-1320] C:\Program Files\D-Link\Wireless G WDA-1320\AirGCFG.exe
O4 - HKLM\..\Run: [ANIWZCS2Service] C:\Program Files\ANI\ANIWZCS2 Service\WZCSLDR2.exe
O4 - HKLM\..\Run: [NvCplDaemon] RUNDLL32.EXE C:\WINDOWS\System32\NvCpl.dll,NvStartup
O4 - HKLM\..\Run: [nwiz] nwiz.exe /install
O4 - HKLM\..\Run: [NvMediaCenter] RUNDLL32.EXE C:\WINDOWS\System32\NvMcTray.dll,NvTaskbarInit
O4 - HKLM\..\Run: [AVG7_CC] C:\PROGRA~1\Grisoft\AVG7\avgcc.exe /STARTUP
O4 - HKLM\..\Run: [SunJavaUpdateSched] "C:\Program Files\Java\jre1.6.0_02\bin\jusched.exe"
O4 - HKLM\..\Run: [QuickTime Task] "C:\Program Files\QuickTime\qttask.exe" -atboottime
O4 - HKLM\..\Run: [TkBellExe] "C:\Program Files\Common Files\Real\Update_OB\realsched.exe" -osboot
O4 - HKLM\..\Run: [Adobe Reader Speed Launcher] "C:\Program Files\Adobe\Reader 8.0\Reader\Reader_sl.exe"
O4 - HKLM\..\Run: [IMJPMIG8.1] "C:\WINDOWS\IME\imjp8_1\IMJPMIG.EXE" /Spoil /RemAdvDef /Migration32
O4 - HKLM\..\Run: [MSPY2002] C:\WINDOWS\System32\IME\PINTLGNT\ImScInst.exe /SYNC
O4 - HKLM\..\Run: [PHIME2002ASync] C:\WINDOWS\System32\IME\TINTLGNT\TINTSETP.EXE /SYNC
O4 - HKLM\..\Run: [PHIME2002A] C:\WINDOWS\System32\IME\TINTLGNT\TINTSETP.EXE /IMEName
O4 - HKLM\..\Run: [FixCamera] C:\WINDOWS\FixCamera.exe
O4 - HKLM\..\Run: [avast!] C:\PROGRA~1\ALWILS~1\Avast4\ashDisp.exe
O4 - HKCU\..\Run: [BitTorrent] "C:\Program Files\BitTorrent\bittorrent.exe" --force_start_minimized
O4 - HKCU\..\Run: [Yahoo! Pager] "C:\PROGRA~1\Yahoo!\MESSEN~1\YAHOOM~1.EXE" -quiet
O4 - HKCU\..\Run: [CTSyncU.exe] "C:\Program Files\Creative\Sync Manager Unicode\CTSyncU.exe"
O4 - HKCU\..\Run: [ctfmon.exe] C:\WINDOWS\System32\ctfmon.exe
O4 - HKCU\..\Run: [MSMSGS] "C:\Program Files\Messenger\MSMSGS.EXE" /background
O4 - HKUS\S-1-5-19\..\Run: [AVG7_Run] C:\PROGRA~1\Grisoft\AVG7\avgw.exe /RUNONCE (User 'LOCAL SERVICE')
O4 - HKUS\S-1-5-20\..\Run: [AVG7_Run] C:\PROGRA~1\Grisoft\AVG7\avgw.exe /RUNONCE (User 'NETWORK SERVICE')
O4 - HKUS\S-1-5-18\..\Run: [AVG7_Run] C:\PROGRA~1\Grisoft\AVG7\avgw.exe /RUNONCE (User 'SYSTEM')
O4 - HKUS\.DEFAULT\..\Run: [AVG7_Run] C:\PROGRA~1\Grisoft\AVG7\avgw.exe /RUNONCE (User 'Default user')
O4 - Startup: Adobe Gamma.lnk = C:\Program Files\Common Files\Adobe\Calibration\Adobe Gamma Loader.exe
O4 - Startup: MSWin--1345148359.exe
O4 - Startup: MSWin--1683815440.exe
O4 - Global Startup: Adobe Gamma Loader.lnk = C:\Program Files\Common Files\Adobe\Calibration\Adobe Gamma Loader.exe
O4 - Global Startup: WinZip Quick Pick.lnk = C:\Program Files\WinZip\WZQKPICK.EXE
O8 - Extra context menu item: E&xport to Microsoft Excel - res://C:\PROGRA~1\MICROS~2\OFFICE11\EXCEL.EXE/3000
O9 - Extra button: Yahoo! Services - {5BAB4B5B-68BC-4B02-94D6-2FC0DE4A7897} - C:\Program Files\Yahoo!\Common\yiesrvc.dll
O9 - Extra button: Research - {92780B25-18CC-41C8-B9BE-3C9C571A8263} - C:\PROGRA~1\MICROS~2\OFFICE11\REFIEBAR.DLL
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
O16 - DPF: {50BD5CDA-4BA8-4048-8FAA-763F222E41D8} - ms-its:mhtml:file://c:\\nores.mht! adxrnet.net/code/chm/xpre.chm::/xpreload.ocx
O16 - DPF: {6414512B-B978-451D-A0D8-FCFDF33E833C} (WUWebControl Class) - www.update.microsoft.com/windowsupdate/v...te.cab?1203477569515
O20 - Winlogon Notify: kerberos4 - C:\WINDOWS\SYSTEM32\msxmtny.dll
O23 - Service: Ad-Aware 2007 Service (aawservice) - Lavasoft - C:\Program Files\Lavasoft\Ad-Aware 2007\aawservice.exe
O23 - Service: Adobe LM Service - Adobe Systems - C:\Program Files\Common Files\Adobe Systems Shared\Service\Adobelmsvc.exe
O23 - Service: ANIWZCSd Service (ANIWZCSdService) - Alpha Networks Inc. - C:\Program Files\ANI\ANIWZCS2 Service\ANIWZCSdS.exe
O23 - Service: avast! iAVS4 Control Service (aswUpdSv) - ALWIL Software - C:\Program Files\Alwil Software\Avast4\aswUpdSv.exe
O23 - Service: avast! Antivirus - ALWIL Software - C:\Program Files\Alwil Software\Avast4\ashServ.exe
O23 - Service: avast! Mail Scanner - ALWIL Software - C:\Program Files\Alwil Software\Avast4\ashMaiSv.exe
O23 - Service: avast! Web Scanner - ALWIL Software - C:\Program Files\Alwil Software\Avast4\ashWebSv.exe
O23 - Service: AVG7 Alert Manager Server (Avg7Alrt) - GRISOFT, s.r.o. - C:\PROGRA~1\Grisoft\AVG7\avgamsvr.exe
O23 - Service: AVG7 Update Service (Avg7UpdSvc) - GRISOFT, s.r.o. - C:\PROGRA~1\Grisoft\AVG7\avgupsvc.exe
O23 - Service: AVG E-mail Scanner (AVGEMS) - GRISOFT, s.r.o. - C:\PROGRA~1\Grisoft\AVG7\avgemc.exe
O23 - Service: NVIDIA Display Driver Service (NVSvc) - NVIDIA Corporation - C:\WINDOWS\System32\nvsvc32.exe

--
End of file - 8393 bytes

I usually suspect overheating components and hardware defects to be the causes of computers restarting.

In one case, simply touching the power supply cable caused the computer to restart -- resolution was to replace the power supply.

In the other cases, adding thermal paste to the CPU resolved the restarting issues.

You need to narrow this down a bit. Try looking for bits of evidence such as:
Does it restart after a set period of time or when a particular thing is done - suggests malware
Does it run okay for a while from cold but restart quicker when it's warm - overheating problem
Waggle all the mains connections to see if it provokes the problem - bad electricity
Take the lid off and using something insulated give everything inside a waggle/prod. If it restarts - hardware problem
Finally when it restarts do you see any error, however briefly, before it does? If so untick 'automatically restart' under the advanced tab of System Properties to capture the error

i agree with the power supply theory. i has a asis tower that constant ly restarted itself. one because the power supply was bad, and two, because teh ground circuit was toast , so if you touched any metal part of the comp, (ie: the usb port casing around the usb terminals) it would restart. id try replacing that sucker.

Maybe something simple. Have you removed the check mark from in System Properties under startup and recovery from Automactically restart under system failure