Normally, I'd start looking at shell execute hooks. does this happen if you restart your computer in safe mode?
In regular mode, do you experience any behavior like your processor usage remaining very high, but no processes are high?

I dont think Subversion should do anything, its only a repository and I dont of any hungry processing it keeps running.

Aside from what oracle has said, other things you could try is a defrag, I do find after I do a defrag, my windows explorer certainly improves speed.
How much disk space have you got left?

Have you checking task manager to see what is using the cpu?

You could also try running hijack this to see what other things are going on

I get this, too. The reason on my computer is mapped network drives. I don't know if your computer is connected to a network or another computer and if you have network shares mapped. But Explorer is poorly designed in this area if you ask me! Every activity in Explorer will refresh all drives, including the mapped drives. So if you are like me and have over 10 mappings, Explorer tries to connect to those network shares every time I do something in there! Very annoying.

The problem goes away if I either am connected to the computers with the network shares or if I remove all mappings I don't need!

Maybe it is the same with your PC?

Cheers

Peter

You know Pete, I bet your exactly right.
Try this out:
open an explorer folder such as "my documents" and from the tools menu select "folder options"
go to the "View" tab and uncheck the first box "automatically search for network folders and printers"
normally this sets these folders to appear in my network places, but it has an affect of making the PC NOT verify connectivity on mapped drives until they're used.

As I said, get a CD/DVD with SQL Server, run the setup on your local machine and select the client tools. This will install the Business Intelligence Projects. If you then open Visual Studio and select "Create Project" you should see Business Intelligence and select Report Project.

Thank you for awarding the points!

Cheers

Peter

Sorry about not getting back on this quicker. The problem sort of dissapeared after a few days and then I didn't get to check your suggestions.
I don't have any mapped drives, but I will take a look at the other things you've pointed me to.

well, now the problem have degraded to slowing the computer in general. This is not only when running, but also the startup process is slower than normal. I'm fearing some hardware problem?
Anyway I have looked at the processes running and none seem to consume all the cpu.
I have noticed now that even when i try to play a music file or watch a video, it's never smooth anymore, but seems to be interrupted every 5-10 sec. most of the time.
I did not defragment the hard disk yet, but I have plenty of space still.
I'll run hijack this and post the result, maybe you can see something there...

Logfile of Trend Micro HijackThis v2.0.0 (BETA)
Scan saved at 12:30:49, on 17/11/2007
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\Ati2evxx.exe
C:\WINDOWS\system32\svchost.exe
C:\WINDOWS\System32\svchost.exe
C:\Program Files\Intel\Wireless\Bin\EvtEng.exe
C:\Program Files\Intel\Wireless\Bin\S24EvMon.exe
E:\Program Files\Lavasoft\Ad-Aware 2007\aawservice.exe
E:\Program Files\Alwil Software\Avast4\aswUpdSv.exe
C:\WINDOWS\system32\Ati2evxx.exe
E:\Program Files\Alwil Software\Avast4\ashServ.exe
C:\WINDOWS\Explorer.EXE
C:\WINDOWS\system32\spoolsv.exe
C:\WINDOWS\System32\acs.exe
C:\Program Files\TortoiseSVN\bin\TSVNCache.exe
C:\PROGRA~1\LAUNCH~1\LManager.exe
C:\Program Files\Synaptics\SynTP\SynTPEnh.exe
C:\WINDOWS\RTHDCPL.EXE
C:\Program Files\ATI Technologies\ATI Control Panel\atiptaxx.exe
E:\PROGRA~1\ALWILS~1\Avast4\ashDisp.exe
C:\WINDOWS\system32\inetsrv\inetinfo.exe
E:\Program Files\Zone Labs\ZoneAlarm\zlclient.exe
c:\Program Files\Common Files\Microsoft Shared\VS7Debug\mdm.exe
C:\Program Files\Intel\Wireless\Bin\RegSrvc.exe
C:\WINDOWS\system32\ctfmon.exe
C:\Program Files\Google\GoogleToolbarNotifier\GoogleToolbarNotifier.exe
C:\Program Files\CyberLink\Shared Files\RichVideo.exe
C:\WINDOWS\system32\slserv.exe
C:\WINDOWS\System32\snmp.exe
C:\WINDOWS\System32\svchost.exe
C:\WINDOWS\system32\ZoneLabs\vsmon.exe
E:\PROGRA~1\MICROS~4\webtool.exe
E:\Program Files\Alwil Software\Avast4\ashSimpl.exe
C:\Program Files\MSN Messenger\usnsvc.exe
E:\Program Files\Microsoft Visual Studio 8\Common7\IDE\devenv.exe
E:\Program Files\Mozilla Firefox\firefox.exe
E:\Program Files\Microsoft Office\OFFICE11\EXCEL.EXE
C:\WINDOWS\System32\dllhost.exe
C:\Program Files\Adobe\Acrobat 7.0\Reader\AcroRd32.exe
C:\Program Files\Microsoft SQL Server\80\Tools\Binn\sqlmangr.exe
E:\PROGRA~1\MICROS~2\MSSQL\binn\sqlservr.exe
C:\WINDOWS\system32\NOTEPAD.EXE
C:\WINDOWS\Microsoft.NET\Framework\v2.0.50727\aspnet_wp.exe
E:\Downloadz\HiJackThis_v2.exe

R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Default_Search_URL = http://go.microsoft.com/fwlink/?LinkId=5...
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Search Bar = http://us.rd.yahoo.com/customize/ie/defa...
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Search Page = http://go.microsoft.com/fwlink/?LinkId=5...
R1 - HKCU\Software\Microsoft\Internet Explorer\SearchURL,(Default) = http://us.rd.yahoo.com/customize/ie/defa...
R1 - HKCU\Software\Microsoft\Internet Connection Wizard,ShellNext = http://windowsupdate.microsoft.com/
O2 - BHO: SSVHelper Class - {761497BB-D6F0-462C-B6EB-D4DAF1D92D43} - C:\Program Files\Java\jre1.5.0_06\bin\ssv.dll
O2 - BHO: (no name) - {7E853D72-626A-48EC-A868-BA8D5E23E045} - (no file)
O2 - BHO: Windows Live Sign-in Helper - {9030D464-4C02-4ABF-8ECC-5164760863C6} - C:\Program Files\Common Files\Microsoft Shared\Windows Live\WindowsLiveLogin.dll
O4 - HKLM\..\Run: [Zone Labs Client] E:\Program Files\Zone Labs\ZoneAlarm\zlclient.exe
O4 - HKLM\..\Run: [High Definition Audio Property Page Shortcut] "HDAShCut.exe"
O4 - HKLM\..\Run: [EPSON Stylus C64 Series] "C:\WINDOWS\System32\spool\DRIVERS\W32X86\3\E_S4I2C1.EXE /P23 " PSON Stylus C64 Series" /O5 "LPT1:" /M "Stylus C64""
O4 - HKLM\..\Run: [LManager] "C:\PROGRA~1\LAUNCH~1\LManager.exe"
O4 - HKLM\..\Run: [SynTPEnh] "C:\Program Files\Synaptics\SynTP\SynTPEnh.exe"
O4 - HKLM\..\Run: [RTHDCPL] "RTHDCPL.EXE"
O4 - HKLM\..\Run: [ATIPTA] C:\Program Files\ATI Technologies\ATI Control Panel\atiptaxx.exe
O4 - HKLM\..\Run: [avast!] E:\PROGRA~1\ALWILS~1\Avast4\ashDisp.exe
O4 - HKLM\..\Run: [ZoneAlarm Client] "E:\Program Files\Zone Labs\ZoneAlarm\zlclient.exe"
O4 - HKCU\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\ctfmon.ex

If you got plenty of space then I recommend you do a defrag. Do this first before other things.

I see you have ZoneAlarm running, try disabling that then see. Obviously this is just a test. At the very least you have windows firewall running so there is something at least to protect yourself a little during this test.

at this point, I agree with nidhi. a simple defrag might be your best bet. There are no startup processes that raise any red flags that I can see. though your hijack this log seems a little short, I suspect the entire post might have been truncated. Things that usually cause slow startup, but do not show up in process usage are services failing to start. checkout your application event log (control panel->administrative tools->event log) to see if there are any failing services.
You can also try disabling some services using msconfig to see if that helps. Lastly, try a windows update to make sure that's on the up and up.

Sorry for not closing this question, guys. thanks a lot for your help.
I'm not sure what the cause of the problem was, but I think it was related to the windows explorer integrated version of Subversion called Tortoise.
I saw that in the task manager, the TSVNCache.exe process was using a lot of CPU when i experienced problems and if I killed the process everything seemed back to normal.