Thank you in advance to anyone looking at this thread.

My PC is running Windows XP and has been fine up until about a month ago. I have Avast! Anti-virus software and Ad-Aware and have run both with full scans and defraged my hard disks and cannot find a solution.
My computer started running sluggishly (I first noticed it while playing songs in iTunes. About ten seconds into every song the audio would be disrupted, sounding like the PC was slowing down) and has become exponentially worse. I have over 6gb free on both hard disks, so it's not a space issue. There are a number of svchost.exe instances running at all times, with one usually around 30,000k. I play games on my computer and where it would take Spore less than a minute to start before, it now takes over three minutes. Please, can someone help me? I don't want to have to re-install windows.

System Specs:
Pentium 4 3.00 Ghz processor
2.5 Gb ram
Windows XP Home edition
Dell Dimension DIM4700

HijackThis logfile:
Logfile of Trend Micro HijackThis v2.0.2
Scan saved at 11:21:12 PM, on 11/7/2009
Platform: Windows XP SP3 (WinNT 5.01.2600)
MSIE: Internet Explorer v7.00 (7.00.6000.16915)
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\Ati2evxx.exe
C:\WINDOWS\system32\svchost.exe
C:\WINDOWS\System32\svchost.exe
C:\Program Files\Alwil Software\Avast4\aswUpdSv.exe
C:\Program Files\Lavasoft\Ad-Aware\AAWService.exe
C:\WINDOWS\system32\Ati2evxx.exe
C:\Program Files\Alwil Software\Avast4\ashServ.exe
C:\WINDOWS\system32\spoolsv.exe
C:\Program Files\Common Files\Apple\Mobile Device Support\bin\AppleMobileDeviceService.exe
C:\WINDOWS\System32\svchost.exe
C:\Program Files\Java\jre6\bin\jqs.exe
C:\WINDOWS\system32\svchost.exe
C:\WINDOWS\system32\Tablet.exe
C:\Program Files\Alwil Software\Avast4\ashMaiSv.exe
C:\Program Files\Alwil Software\Avast4\ashWebSv.exe
C:\WINDOWS\Explorer.EXE
C:\Program Files\ATI Technologies\ATI.ACE\Core-Static\MOM.exe
C:\PROGRA~1\ALWILS~1\Avast4\ashDisp.exe
C:\Program Files\iTunes\iTunesHelper.exe
C:\WINDOWS\system32\ctfmon.exe
C:\Program Files\Windows Media Player\WMPNSCFG.exe
C:\Program Files\iPod\bin\iPodService.exe
C:\Program Files\ATI Technologies\ATI.ACE\Core-Static\ccc.exe
C:\Program Files\Java\jre6\bin\jusched.exe
C:\Program Files\Mozilla Firefox\firefox.exe
C:\Program Files\Trend Micro\HijackThis\HijackThis.exe

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
O2 - BHO: Adobe PDF Reader Link Helper - {06849E9F-C8D7-4D59-B87D-784B7D6BE0B3} - C:\Program Files\Adobe\Acrobat 7.0\ActiveX\AcroIEHelper.dll
O2 - BHO: SSVHelper Class - {761497BB-D6F0-462C-B6EB-D4DAF1D92D43} - C:\Program Files\Java\jre6\bin\ssv.dll
O2 - BHO: Adobe PDF Conversion Toolbar Helper - {AE7CD045-E861-484f-8273-0445EE161910} - C:\Program Files\Adobe\Acrobat 7.0\Acrobat\AcroIEFavClient.dll
O2 - BHO: Java(tm) Plug-In 2 SSV Helper - {DBC80044-A445-435b-BC74-9C25C1C588A9} - C:\Program Files\Java\jre6\bin\jp2ssv.dll
O2 - BHO: JQSIEStartDetectorImpl - {E7E6F031-17CE-4C07-BC86-EABFE594F69C} - C:\Program Files\Java\jre6\lib\deploy\jqs\ie\jqs_plugin.dll
O3 - Toolbar: Adobe PDF - {47833539-D0C5-4125-9FA8-0819E2EAAC93} - C:\Program Files\Adobe\Acrobat 7.0\Acrobat\AcroIEFavClient.dll
O4 - HKLM\..\Run: [Rainlendar] "c:\program files\rainlendar\rainlendar.exe"
O4 - HKLM\..\Run: [StartCCC] "C:\Program Files\ATI Technologies\ATI.ACE\Core-Static\CLIStart.exe" MSRun
O4 - HKLM\..\Run: [avast!] C:\PROGRA~1\ALWILS~1\Avast4\ashDisp.exe
O4 - HKLM\..\Run: [iTunesHelper] "C:\Program Files\iTunes\iTunesHelper.exe"
O4 - HKLM\..\Run: [SunJavaUpdateSched] "C:\Program Files\Java\jre6\bin\jusched.exe"
O4 - HKCU\..\Run: [ctfmon.exe] C:\WINDOWS\system32\ctfmon.exe
O4 - HKCU\..\Run: [WMPNSCFG] C:\Program Files\Windows Media Player\WMPNSCFG.exe
O4 - HKUS\S-1-5-18\..\Run: [DWQueuedReporting] "C:\PROGRA~1\COMMON~1\MICROS~1\DW\dwtrig20.exe" -t (User 'SYSTEM')
O4 - HKUS\.DEFAULT\..\Run: [DWQueuedReporting] "C:\PROGRA~1\COMMON~1\MICROS~1\DW\dwtrig20.exe" -t (User 'Default user')
O4 - Global Startup: Adobe Gamma Loader.lnk = C:\Program Files\Common Files\Adobe\Calibration\Adobe Gamma Loader.exe
O4 - Global Startup: Adobe Gamma.lnk = C:\Program Files\Common Files\Adobe\Calibration\Adobe Gamma Loader.exe
O8 - Extra context menu item: Convert link target to Adobe PDF - res://C:\Program Files\Adobe\Acrobat 7.0\Acrobat\AcroIEFavClient.dll/AcroIECapture.html
O8 - Extra context menu item: Convert link target to existing PDF - res://C:\Program Files\Adobe\Acrobat 7.0\Acrobat\AcroIEFavClient.dll/AcroIEAppend.html
O8 - Extra context menu item: Convert selected links to Adobe PDF - res://C:\Program Files\Adobe\Acrobat 7.0\Acrobat\AcroIEFavClient.dll/AcroIECaptureSelLinks.html
O8 - Extra context menu item: Convert selected links to existing PDF - res://C:\Program Files\Adobe\Acrobat 7.0\Acrobat\AcroIEFavClient.dll/AcroIEAppendSelLinks.html
O8 - Extra context menu item: Convert selection to Adobe PDF - res://C:\Program Files\Adobe\Acrobat 7.0\Acrobat\AcroIEFavClient.dll/AcroIECapture.html
O8 - Extra context menu item: Convert selection to existing PDF - res://C:\Program Files\Adobe\Acrobat 7.0\Acrobat\AcroIEFavClient.dll/AcroIEAppend.html
O8 - Extra context menu item: Convert to Adobe PDF - res://C:\Program Files\Adobe\Acrobat 7.0\Acrobat\AcroIEFavClient.dll/AcroIECapture.html
O8 - Extra context menu item: Convert to existing PDF - res://C:\Program Files\Adobe\Acrobat 7.0\Acrobat\AcroIEFavClient.dll/AcroIEAppend.html
O8 - Extra context menu item: E&xport to Microsoft Excel - res://C:\PROGRA~1\MICROS~4\Office10\EXCEL.EXE/3000
O9 - Extra button: (no name) - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Program Files\Java\jre6\bin\npjpi160_17.dll
O9 - Extra 'Tools' menuitem: Sun Java Console - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Program Files\Java\jre6\bin\npjpi160_17.dll
O9 - Extra button: Real.com - {CD67F990-D8E9-11d2-98FE-00C0F0318AFE} - C:\WINDOWS\system32\Shdocvw.dll
O9 - Extra button: (no name) - {e2e2dd38-d088-4134-82b7-f2ba38496583} - C:\WINDOWS\Network Diagnostic\xpnetdiag.exe
O9 - Extra 'Tools' menuitem: @xpsp3res.dll,-20001 - {e2e2dd38-d088-4134-82b7-f2ba38496583} - C:\WINDOWS\Network Diagnostic\xpnetdiag.exe
O9 - Extra button: PartyPoker.net - {F4430FE8-2638-42e5-B849-800749B94EED} - C:\Games\PartyGaming.Net\PartyPokerNet\RunPF.exe (file missing)
O9 - Extra 'Tools' menuitem: PartyPoker.net - {F4430FE8-2638-42e5-B849-800749B94EED} - C:\Games\PartyGaming.Net\PartyPokerNet\RunPF.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
O16 - DPF: {17492023-C23A-453E-A040-C7C580BBF700} (Windows Genuine Advantage Validation Tool) - http://go.microsoft.com/fwlink/?linkid=39204
O16 - DPF: {27527D31-447B-11D5-A46E-0001023B4289} (CoGSManager Class) - http://gamingzone.ubisoft.com/dev/pa.../GSManager.cab
O16 - DPF: {5F8469B4-B055-49DD-83F7-62B522420ECC} (Facebook Photo Uploader Control) - http://upload.facebook.com/controls/...toUploader.cab
O16 - DPF: {6E32070A-766D-4EE6-879C-DC1FA91D2FC3} (MUWebControl Class) - http://update.microsoft.com/microsof...?1120344345312
O16 - DPF: {CD995117-98E5-4169-9920-6C12D4C0B548} - http://gamedownload.ijjimax.com/game...Plugin9USA.cab
O23 - Service: Adobe LM Service - Adobe Systems - C:\Program Files\Common Files\Adobe Systems Shared\Service\Adobelmsvc.exe
O23 - Service: Apple Mobile Device - Apple Inc. - C:\Program Files\Common Files\Apple\Mobile Device Support\bin\AppleMobileDeviceService.exe
O23 - Service: avast! iAVS4 Control Service (aswUpdSv) - ALWIL Software - C:\Program Files\Alwil Software\Avast4\aswUpdSv.exe
O23 - Service: Ati HotKey Poller - ATI Technologies Inc. - C:\WINDOWS\system32\Ati2evxx.exe
O23 - Service: ATI Smart - Unknown owner - C:\WINDOWS\SYSTEM32\ati2sgag.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: InstallDriver Table Manager (IDriverT) - Macrovision Corporation - C:\Program Files\Common Files\InstallShield\Driver\11\Intel 32\IDriverT.exe
O23 - Service: iPod Service - Apple Inc. - C:\Program Files\iPod\bin\iPodService.exe
O23 - Service: Java Quick Starter (JavaQuickStarterService) - Sun Microsystems, Inc. - C:\Program Files\Java\jre6\bin\jqs.exe
O23 - Service: Lavasoft Ad-Aware Service - Lavasoft - C:\Program Files\Lavasoft\Ad-Aware\AAWService.exe
O23 - Service: Intel NCS NetService (NetSvc) - Intel(R) Corporation - C:\Program Files\Intel\PROSetWired\NCS\Sync\NetSvc.exe
O23 - Service: TabletService - Wacom Technology, Corp. - C:\WINDOWS\system32\Tablet.exe

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