Computer keeps locking up

My computer keeps locking up and I don't know why. I've done full scans with Avast and Ad-Aware and still the same.

Logfile of Trend Micro HijackThis v2.0.4
Scan saved at 1:45:57 PM, on 7/22/2011
Platform: Windows Vista SP2 (WinNT 6.00.1906)
MSIE: Internet Explorer v9.00 (9.00.8112.16421)
Boot mode: Normal

Running processes:
C:\Windows\system32\Dwm.exe
C:\Windows\Explorer.EXE
C:\Windows\system32\taskeng.exe
C:\Program Files\Alwil Software\Avast5\AvastUI.exe
C:\Program Files\Synaptics\SynTP\SynTPEnh.exe
C:\Program Files\Common Files\Java\Java Update\jusched.exe
C:\Program Files\Mozilla Firefox\firefox.exe
C:\Program Files\Mozilla Firefox\plugin-container.exe
C:\Program Files\Mozilla Firefox\plugin-container.exe
C:\Program Files\Mozilla Firefox\plugin-container.exe
C:\Program Files\Mozilla Firefox\plugin-container.exe
C:\Program Files\Mozilla Firefox\plugin-container.exe
C:\Program Files\Mozilla Firefox\plugin-container.exe
C:\Users\markg\Desktop\HijackThis.exe

R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Search Page = http://go.microsoft.com/fwlink/?LinkId=54896
R0 - HKLM\Software\Microsoft\Internet Explorer\Search,SearchAssistant =
R0 - HKLM\Software\Microsoft\Internet Explorer\Search,CustomizeSearch =
R1 - HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings,ProxyOverride = *.local
R0 - HKCU\Software\Microsoft\Internet Explorer\Toolbar,LinksFolderName =
O2 - BHO: AcroIEHelperStub - {18DF081C-E8AD-4283-A596-FA578C2EBDC3} - C:\Program Files\Common Files\Adobe\Acrobat\ActiveX\AcroIEHelperShim.dll
O2 - BHO: RealPlayer Download and Record Plugin for Internet Explorer - {3049C3E9-B461-4BC5-8870-4C09146192CA} - C:\ProgramData\Real\RealPlayer\BrowserRecordPlugin\IE\rpbrowserrecordplugin.dll
O2 - BHO: Java(tm) Plug-In 2 SSV Helper - {DBC80044-A445-435b-BC74-9C25C1C588A9} - C:\Program Files\Java\jre6\bin\jp2ssv.dll
O4 - HKLM\..\Run: [avast5] "C:\Program Files\Alwil Software\Avast5\avastUI.exe" /nogui
O4 - HKLM\..\Run: [SynTPEnh] C:\Program Files\Synaptics\SynTP\SynTPEnh.exe
O4 - HKLM\..\Run: [SunJavaUpdateSched] "C:\Program Files\Common Files\Java\Java Update\jusched.exe"
O4 - HKLM\..\Run: [Adobe ARM] "C:\Program Files\Common Files\Adobe\ARM\1.0\AdobeARM.exe"
O4 - HKUS\S-1-5-20\..\Run: [WindowsWelcomeCenter] rundll32.exe oobefldr.dll,ShowWelcomeCenter (User 'NETWORK SERVICE')
O11 - Options group: [ACCELERATED_GRAPHICS] Accelerated graphics
O12 - Plugin for .mu3: C:\Program Files\Internet Explorer\Plugins\NPMyrMus.dll
O12 - Plugin for .mus: C:\Program Files\Internet Explorer\Plugins\NPMyrMus.dll
O12 - Plugin for .mxl: C:\Program Files\Internet Explorer\Plugins\NPMyrMus.dll
O12 - Plugin for .mya: C:\Program Files\Internet Explorer\Plugins\NPMyrMus.dll
O12 - Plugin for .myr: C:\Program Files\Internet Explorer\Plugins\NPMyrMus.dll
O12 - Plugin for .myt: C:\Program Files\Internet Explorer\Plugins\NPMyrMus.dll
O12 - Plugin for .xmz: C:\Program Files\Internet Explorer\Plugins\NPMyrMus.dll
O16 - DPF: {D27CDB6E-AE6D-11CF-96B8-444553540000} (Shockwave Flash Object) - http://fpdownload2.macromedia.com/get/s ... wflash.cab
O22 - SharedTaskScheduler: Component Categories cache daemon - {8C7461EF-2B13-11d2-BE35-3078302C2030} - C:\Windows\system32\browseui.dll
O23 - Service: Apple Mobile Device - Apple Inc. - C:\Program Files\Common Files\Apple\Mobile Device Support\AppleMobileDeviceService.exe
O23 - Service: Ati External Event Utility - ATI Technologies Inc. - C:\Windows\system32\Ati2evxx.exe
O23 - Service: avast! Antivirus - AVAST Software - C:\Program Files\Alwil Software\Avast5\AvastSvc.exe
O23 - Service: Bonjour Service - Apple Inc. - C:\Program Files\Bonjour\mDNSResponder.exe
O23 - Service: FLEXnet Licensing Service - Acresso Software Inc. - C:\Program Files\Common Files\Macrovision Shared\FLEXnet Publisher\FNPLicensingService.exe
O23 - Service: Google Update Service (gupdate) (gupdate) - Google Inc. - C:\Program Files\Google\Update\GoogleUpdate.exe
O23 - Service: iPod Service - Apple Inc. - C:\Program Files\iPod\bin\iPodService.exe
O23 - Service: Lavasoft Ad-Aware Service - Lavasoft Limited - C:\Program Files\Lavasoft\Ad-Aware\AAWService.exe

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End of file - 4109 bytes

Hi markg,
Locking up can be caused by malware or a hardware problem.
We will try to identify the source so you can make corrections.
-----------------------------------------
Check hard Drive for Errors
Open Notepad... then copy and paste the following line into Notepad:
(Notepad is in Start, Programs, Accessories)

cmd  /c  chkdsk  c:  |find  /v  "percent"  >> "%userprofile%\desktop\checkhd.txt"

Now Save the NotePad file like this:

• Click on File from the top menu bar.
• Select Save As, use Filename: testhd.bat and Save As Type: All Files.
• Choose Desktop as the location
• Click Save.

Right click on testhd.bat on your desktop and select Run As Administrator to run it. OK the UAC.
A Command Prompt box will pop up, then close after a couple minutes.
Please post the contents of the checkhd.txt file from your desktop.
If the file is very long, just copy and paste the LAST 20 or 30 lines into your reply.
---------------------------------------------
Download the OTL Scanner
Please download OTL.exe by OldTimer and save it to your desktop.
---------------------------------------------
Run a Scan with OTL

• For Vista, right click the OTL icon and choose "Run as administrator".
• Check the boxes labeled :
  • Scan All Users
  • LOP check
  • Purity check
• Make sure all other windows are closed to let it run uninterrupted.
• Click on the Run Scan button at the top left hand corner. Do not change any settings unless otherwise told to do so. The scan wont take long.

When the scan completes, it will open two notepad windows. OTL.Txt and Extras.Txt. These are saved in the same location as OTL. (desktop)
The Extras.txt file will only appear the very first time you run OTL.
Please copy (Edit->Select All, Edit->Copy) the contents of these files, one at a time, and post them as a reply. Use separate replies if more convenient.

askey127

Lack of Response,