Log's clean. Suggest overheating, or dodgy PSU as first items to check.

Thanks so much gerbil! I'll look into your suggestions.

I think there are many programs running in the background. There aren't needed upon starting your windows. You can run all the programs manually. Try to disable some of them in the System Configuration Utility.

Start-Run-then type "msconfig". Uncheck all items found in the "Startup" except from your firewall and antivirus programs.

Clean all fans inside the cpu unit especially the processor fan and its heatsink. Additional case fan is also needed to dissipate heat and retain the room temperature inside the cpu unit.

If you have a spare power supply, try to swap it into your system so that you can determine if your power supply is not functioning very well.

Thanks fren. The shut-offs are still happening, and what's worse is that my computer cannot use any of the restore points (it says, after going through the motions and restarting, that is could not bring my PC back to any of the restore points).

I should also mention 2 things: I'm using a laptop, and I'm a little worried about messing with things I'm not that familiar with, i.e. registry, SCU, etc. Besides, once I get back to school, the university makes you install a CD that takes control of your PC and re-installs all their crap again.

Here's another log I ran right after start-up. It looks about the same to me:

Logfile of HijackThis v1.99.1
Scan saved at 5:21:38 PM, on 7/31/2007
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\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\Common Files\Symantec Shared\ccEvtMgr.exe
C:\Program Files\Common Files\Symantec Shared\ccSetMgr.exe
C:\Program Files\Common Files\Symantec Shared\SNDSrvc.exe
C:\WINDOWS\system32\spoolsv.exe
C:\WINDOWS\Explorer.EXE
C:\WINDOWS\System32\PackethSvc.exe
C:\WINDOWS\System32\Ati2evxx.exe
C:\Program Files\Symantec\LiveUpdate\ALUSchedulerSvc.exe
C:\Program Files\Symantec AntiVirus\DefWatch.exe
C:\Program Files\Symantec AntiVirus\Rtvscan.exe
C:\WINDOWS\wanmpsvc.exe
C:\WINDOWS\system32\atiptaxx.exe
C:\Program Files\Synaptics\SynTP\SynTPLpr.exe
C:\Program Files\Synaptics\SynTP\SynTPEnh.exe
C:\Program Files\Compaq\EAB\EabServr.exe
C:\WINDOWS\system32\wuauclt.exe
C:\Program Files\Common Files\Real\Update_OB\evntsvc.exe
C:\Program Files\Common Files\Symantec Shared\ccApp.exe
C:\PROGRA~1\SYMANT~1\VPTray.exe
C:\Program Files\iTunes\iTunesHelper.exe
C:\Program Files\iPod\bin\iPodService.exe
C:\Program Files\NETGEAR\MA111 Configuration Utility\wlancfg4.exe
C:\Program Files\Common Files\Microsoft Shared\Works Shared\wkcalrem.exe
C:\Program Files\Resnet Configuration Utility\HijackThis.exe

R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Default_Page_URL = https://restech.baylor.edu
R0 - HKLM\Software\Microsoft\Internet Explorer\Main,Start Page = https://restech.baylor.edu
O2 - BHO: AcroIEHlprObj Class - {06849E9F-C8D7-4D59-B87D-784B7D6BE0B3} - C:\Program Files\Adobe\Acrobat 5.0\Reader\ActiveX\AcroIEHelper.ocx
O2 - BHO: (no name) - {FDD3B846-8D59-4ffb-8758-209B6AD74ACC} - c:\Program Files\Microsoft Money\System\mnyviewer.dll
O4 - HKLM\..\Run: [ATIModeChange] Ati2mdxx.exe
O4 - HKLM\..\Run: [AtiPTA] atiptaxx.exe
O4 - HKLM\..\Run: [SynTPLpr] C:\Program Files\Synaptics\SynTP\SynTPLpr.exe
O4 - HKLM\..\Run: [SynTPEnh] C:\Program Files\Synaptics\SynTP\SynTPEnh.exe
O4 - HKLM\..\Run: [eabconfg.cpl] C:\Program Files\Compaq\EAB\EabServr.exe /Start
O4 - HKLM\..\Run: [srmclean] C:\Cpqs\Scom\srmclean.exe
O4 - HKLM\..\Run: [TkBellExe] C:\Program Files\Common Files\Real\Update_OB\evntsvc.exe -osboot
O4 - HKLM\..\Run: [Microsoft Works Portfolio] C:\Program Files\Microsoft Works\WksSb.exe /AllUsers
O4 - HKLM\..\Run: [Microsoft Works Update Detection] C:\Program Files\Microsoft Works\WkDetect.exe
O4 - HKLM\..\Run: [Cpqset] c:\compaq\cpqsetup\cpqset.exe
O4 - HKLM\..\Run: [ccApp] "C:\Program Files\Common Files\Symantec Shared\ccApp.exe"
O4 - HKLM\..\Run: [vptray] C:\PROGRA~1\SYMANT~1\VPTray.exe
O4 - HKLM\..\Run: [iTunesHelper] "C:\Program Files\iTunes\iTunesHelper.exe"
O4 - HKLM\..\Run: [QuickTime Task] "C:\Program Files\QuickTime\qttask.exe" -atboottime
O4 - HKLM\..\RunOnce: ["C:\Program Files\residential technology configuration utility 7.21\client101\sevinst.exe"] "C:\Program Files\residential technology configuration utility 7.21\client101\sevinst.exe" /q NAVNT
O4 - Global Startup: Adobe Gamma Loader.exe.lnk = C:\Program Files\Common Files\Adobe\Calibration\Adobe Gamma Loader.exe
O4 - Global Startup: MA111 Configuration Utility.lnk = ?
O4 - Global Startup: Microsoft Works Calendar Reminders.lnk = ?
O6 - HKCU\Software\Policies\Microsoft\Internet Explorer\Restrictions present
O6 - HKCU\Software\Policies\Microsoft\Internet Explorer\Control Panel present
O9 - Extra button: Yahoo! Login - {2499216C-4BA5-11D5-BD9C-000103C116D5} - C:\Program Files\Yahoo!\Common\ylogin.dll
O9 - Extra 'Tools' menuitem: Yahoo! Login - {2499216C-4BA5-11D5-BD9C-000103C116D5} - C:\Program Files\Yahoo!\Common\ylogin.dll
O9 - Extra button: Messenger - {4528BBE0-4E08-11D5-AD55-00010333D0AD} - C:\Program Files\Yahoo!\Messenger\yhexbmes.dll
O9 - Extra 'Tools' menuitem: Yahoo! Messenger - {4528BBE0-4E08-11D5-AD55-00010333D0AD} - C:\Program Files\Yahoo!\Messenger\yhexbmes.dll
O9 - Extra button: AIM - {AC9E2541-2814-11d5-BC6D-00B0D0A1DE45} - C:\Program Files\AIM\aim.exe
O9 - Extra button: (no name) - {c95fe080-8f5d-11d2-a20b-00aa003c157a} - C:\WINDOWS\System32\shdocvw.dll
O9 - Extra button: Real.com - {CD67F990-D8E9-11d2-98FE-00C0F0318AFE} - C:\WINDOWS\System32\Shdocvw.dll
O9 - Extra button: MoneySide - {E023F504-0C5A-4750-A1E7-A9046DEA8A21} - c:\Program Files\Microsoft Money\System\mnyviewer.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
O9 - Extra button: Advisor - {4AAC555D-352C-4029-ABE8-F06ED9BC532D} - C:\Program Files\COMPAQ\Compaq Advisor\bin\rbaLauncher.exe (HKCU)
O12 - Plugin for .spop: C:\Program Files\Internet Explorer\Plugins\NPDocBox.dll
O14 - IERESET.INF: START_PAGE_URL=https://restech.baylor.edu
O14 - IERESET.INF: MS_START_PAGE_URL=https://resnet.baylor.edu
O15 - Trusted Zone: http://bigdog.baylor.edu
O15 - Trusted Zone: http://burs4.baylor.edu
O15 - Trusted Zone: http://its01.baylor.edu
O15 - Trusted Zone: http://mail.baylor.edu
O15 - Trusted Zone: http://psoftwt.baylor.edu
O15 - Trusted Zone: http://raymond.baylor.edu
O15 - Trusted Zone: http://rmsweb.baylor.edu
O15 - Trusted Zone: http://*.baylor.edu
O15 - Trusted Zone: http://bigdog.baylor.edu (HKLM)
O15 - Trusted Zone: http://burs4.baylor.edu (HKLM)
O15 - Trusted Zone: http://its01.baylor.edu (HKLM)
O15 - Trusted Zone: http://mail.baylor.edu (HKLM)
O15 - Trusted Zone: http://psoftwt.baylor.edu (HKLM)
O15 - Trusted Zone: http://raymond.baylor.edu (HKLM)
O15 - Trusted Zone: http://rmsweb.baylor.edu (HKLM)
O15 - Trusted Zone: http://*.baylor.edu (HKLM)
O20 - Winlogon Notify: NavLogon - C:\WINDOWS\system32\NavLogon.dll
O23 - Service: Ati HotKey Poller - Unknown owner - C:\WINDOWS\System32\Ati2evxx.exe
O23 - Service: Automatic LiveUpdate Scheduler - Symantec Corporation - C:\Program Files\Symantec\LiveUpdate\ALUSchedulerSvc.exe
O23 - Service: Symantec Event Manager (ccEvtMgr) - Symantec Corporation - C:\Program Files\Common Files\Symantec Shared\ccEvtMgr.exe
O23 - Service: Symantec Password Validation (ccPwdSvc) - Symantec Corporation - C:\Program Files\Common Files\Symantec Shared\ccPwdSvc.exe
O23 - Service: Symantec Settings Manager (ccSetMgr) - Symantec Corporation - C:\Program Files\Common Files\Symantec Shared\ccSetMgr.exe
O23 - Service: Compaq Advisor (Compaq_RBA) - NeoPlanet - C:\Program Files\Compaq\Compaq Advisor\bin\compaq-rba.exe
O23 - Service: Symantec AntiVirus Definition Watcher (DefWatch) - Symantec Corporation - C:\Program Files\Symantec AntiVirus\DefWatch.exe
O23 - Service: InstallDriver Table Manager (IDriverT) - Macrovision Corporation - C:\Program Files\Common Files\InstallShield\Driver\11\Intel 32\IDriverT.exe
O23 - Service: iPodService - Apple Computer, Inc. - C:\Program Files\iPod\bin\iPodService.exe
O23 - Service: LiveUpdate - Symantec Corporation - C:\PROGRA~1\Symantec\LIVEUP~1\LUCOMS~1.EXE
O23 - Service: Virtual NIC Service (PackethSvc) - America Online, Inc. - C:\WINDOWS\System32\PackethSvc.exe
O23 - Service: SAVRoam (SavRoam) - symantec - C:\Program Files\Symantec AntiVirus\SavRoam.exe
O23 - Service: Symantec Network Drivers Service (SNDSrvc) - Symantec Corporation - C:\Program Files\Common Files\Symantec Shared\SNDSrvc.exe
O23 - Service: Symantec SPBBCSvc (SPBBCSvc) - Symantec Corporation - C:\Program Files\Common Files\Symantec Shared\SPBBC\SPBBCSvc.exe
O23 - Service: Symantec AntiVirus - Symantec Corporation - C:\Program Files\Symantec AntiVirus\Rtvscan.exe
O23 - Service: WAN Miniport (ATW) Service (WANMiniportService) - America Online, Inc. - C:\WINDOWS\wanmpsvc.exe

I appreciate the continued help. This is really starting to get in the way.

Log's clean still.