I've been having this problem when I use IE or Firefox. I will be on any random site and during operation, the window just closes without any warning and all the windows/tabs for the program disappear. Its not doing it everytime but a few times more than I can handle with frustration. Any idea on what the problem is? I wasnt introduced to computers yesterday and I know that it isnt something apparent with spyware.
It wouldnt permiet me to upload a hijack log but here is one for everyone:
Logfile of Trend Micro HijackThis v2.0.0 (BETA)
Scan saved at 11:26:34 AM, on 8/31/2007
Platform: Windows XP SP2 (WinNT 5.01.2600)
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:\WINDOWS\system32\svchost.exe
C:\WINDOWS\system32\spoolsv.exe
C:\WINDOWS\system32\nvsvc32.exe
C:\WINDOWS\system32\HPZipm12.exe
C:\WINDOWS\System32\svchost.exe
C:\Program Files\Viewpoint\Common\ViewpointService.exe
C:\Program Files\Webroot\Spy Sweeper\SpySweeper.exe
C:\Program Files\Webroot\Washer\WasherSvc.exe
C:\WINDOWS\Explorer.EXE
C:\WINDOWS\system32\WgaTray.exe
C:\Program Files\Internet Explorer\iexplore.exe
C:\Documents and Settings\~\Desktop\HiJackThis_v2.exe

R0 - HKLM\Software\Microsoft\Internet Explorer\Main,Start Page = about:blank
R1 - HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings,ProxyOverride = localhost
O2 - BHO: SSVHelper Class - {761497BB-D6F0-462C-B6EB-D4DAF1D92D43} - C:\Program Files\Java\jre1.6.0_02\bin\ssv.dll
O2 - BHO: (no name) - {7E853D72-626A-48EC-A868-BA8D5E23E045} - (no file)
O4 - HKLM\..\Run: [NvCplDaemon] RUNDLL32.EXE C:\WINDOWS\system32\NvCpl.dll,NvStartup
O9 - Extra button: (no name) - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Program Files\Java\jre1.6.0_02\bin\ssv.dll
O9 - Extra 'Tools' menuitem: Sun Java Console - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Program Files\Java\jre1.6.0_02\bin\ssv.dll
O22 - SharedTaskScheduler: Browseui preloader - {438755C2-A8BA-11D1-B96B-00A0C90312E1} - C:\WINDOWS\System32\browseui.dll
O22 - SharedTaskScheduler: Component Categories cache daemon - {8C7461EF-2B13-11d2-BE35-3078302C2030} - C:\WINDOWS\System32\browseui.dll
O23 - Service: a-squared Free Service (a2free) - Emsi Software GmbH - C:\Documents and Settings\~\Desktop\A-Squared\a-squared Free\a2service.exe
O23 - Service: Google Updater Service (gusvc) - Google - C:\Program Files\Google\Common\Google Updater\GoogleUpdaterService.exe
O23 - Service: NVIDIA Display Driver Service (NVSvc) - NVIDIA Corporation - C:\WINDOWS\system32\nvsvc32.exe
O23 - Service: Panda Process Protection Service (PavPrSrv) - Unknown owner - C:\Program Files\Common Files\Panda Software\PavShld\pavprsrv.exe
O23 - Service: Pml Driver HPZ12 - HP - C:\WINDOWS\system32\HPZipm12.exe
O23 - Service: Viewpoint Manager Service - Viewpoint Corporation - C:\Program Files\Viewpoint\Common\ViewpointService.exe
O23 - Service: Webroot Spy Sweeper Engine (WebrootSpySweeperService) - Webroot Software, Inc. - C:\Program Files\Webroot\Spy Sweeper\SpySweeper.exe
O23 - Service: Window Washer Engine (wwEngineSvc) - Webroot Software, Inc. - C:\Program Files\Webroot\Washer\WasherSvc.exe

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I'm not trained in these, but would point out that you are running HJT from a non-recommended location, it should be installed in it's own folder, normally C:\Program Files\HijackThis.
The only oddball there I see is the ViewpointService.exe.
Google informs me that while this isn't definitely malware, it's a potentially unwanted program, referred to at one source as "foistware", (often installed by/as part of AOL.)
If you don't get more authoritave advice, I'd try removing it.

Just delete that copy of hijackthis you have. Download and install the newest version here:
http://www.filehippo.com/download_hijackthis/ (it automatically puts itself in the right location)

Post a hijackthis log with the newest version.

Logfile of Trend Micro HijackThis v2.0.2
Scan saved at 4:37:09 PM, on 9/8/2007
Platform: Windows XP SP2 (WinNT 5.01.2600)
MSIE: Internet Explorer v6.00 SP2 (6.00.2900.2180)
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:\WINDOWS\system32\svchost.exe
C:\WINDOWS\system32\spoolsv.exe
C:\WINDOWS\system32\nvsvc32.exe
C:\WINDOWS\system32\HPZipm12.exe
C:\WINDOWS\System32\svchost.exe
C:\Program Files\Viewpoint\Common\ViewpointService.exe
C:\Program Files\Webroot\Spy Sweeper\SpySweeper.exe
C:\Program Files\Webroot\Washer\WasherSvc.exe
C:\WINDOWS\system32\WgaTray.exe
C:\WINDOWS\Explorer.EXE
C:\Program Files\Yahoo!\Messenger\ymsgr_tray.exe
C:\Program Files\Trend Micro\HijackThis\HijackThis.exe

R0 - HKLM\Software\Microsoft\Internet Explorer\Main,Start Page = about:blank
R1 - HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings,ProxyOverride = localhost
R3 - URLSearchHook: Yahoo! Toolbar - {EF99BD32-C1FB-11D2-892F-0090271D4F88} - C:\PROGRA~1\Yahoo!\Companion\Installs\cpn10\yt.dll
O2 - BHO: &Yahoo! Toolbar Helper - {02478D38-C3F9-4EFB-9B51-7695ECA05670} - C:\PROGRA~1\Yahoo!\Companion\Installs\cpn10\yt.dll
O2 - BHO: SSVHelper Class - {761497BB-D6F0-462C-B6EB-D4DAF1D92D43} - C:\Program Files\Java\jre1.6.0_02\bin\ssv.dll
O2 - BHO: (no name) - {7E853D72-626A-48EC-A868-BA8D5E23E045} - (no file)
O3 - Toolbar: Yahoo! Toolbar - {EF99BD32-C1FB-11D2-892F-0090271D4F88} - C:\PROGRA~1\Yahoo!\Companion\Installs\cpn10\yt.dll
O4 - HKLM\..\Run: [NvCplDaemon] RUNDLL32.EXE C:\WINDOWS\system32\NvCpl.dll,NvStartup
O4 - HKCU\..\Run: [Yahoo! Pager] "C:\Program Files\Yahoo!\Messenger\YahooMessenger.exe" -quiet
O4 - HKUS\S-1-5-21-515967899-343818398-682003330-1005\..\Run: [Yahoo! Pager] "C:\Program Files\Yahoo!\Messenger\YahooMessenger.exe" -quiet (User '?')
O9 - Extra button: (no name) - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Program Files\Java\jre1.6.0_02\bin\ssv.dll
O9 - Extra 'Tools' menuitem: Sun Java Console - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Program Files\Java\jre1.6.0_02\bin\ssv.dll
O9 - Extra button: (no name) - {5BAB4B5B-68BC-4B02-94D6-2FC0DE4A7897} - (no file)
O16 - DPF: {30528230-99f7-4bb4-88d8-fa1d4f56a2ab} (Installation Support) - C:\Program Files\Yahoo!\Common\Yinsthelper.dll
O23 - Service: a-squared Free Service (a2free) - Emsi Software GmbH - C:\Documents and Settings\~\Desktop\A-Squared\a-squared Free\a2service.exe
O23 - Service: Google Updater Service (gusvc) - Google - C:\Program Files\Google\Common\Google Updater\GoogleUpdaterService.exe
O23 - Service: NVIDIA Display Driver Service (NVSvc) - NVIDIA Corporation - C:\WINDOWS\system32\nvsvc32.exe
O23 - Service: Panda Process Protection Service (PavPrSrv) - Panda Software - C:\Program Files\Common Files\Panda Software\PavShld\pavprsrv.exe
O23 - Service: Pml Driver HPZ12 - HP - C:\WINDOWS\system32\HPZipm12.exe
O23 - Service: Viewpoint Manager Service - Viewpoint Corporation - C:\Program Files\Viewpoint\Common\ViewpointService.exe
O23 - Service: Webroot Spy Sweeper Engine (WebrootSpySweeperService) - Webroot Software, Inc. - C:\Program Files\Webroot\Spy Sweeper\SpySweeper.exe
O23 - Service: Window Washer Engine (wwEngineSvc) - Webroot Software, Inc. - C:\Program Files\Webroot\Washer\WasherSvc.exe

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