[Unknown_Sniper]

I have been having this weird problem with my computer. About a week ago I noticed my computer running way to slow. I hit ctrl+alt+delete and noticed that one of my svchost.exe processes was taking up 95%+ of my processing. I stoped it and my computer started to shut down. did the little shutdown - a thing to turn it off and bam my computer worked and wasnt screwed up for about half a week. Last night it came back. Now when I get rid of the Svchost I cant open up and desktop files, copy and paste links or text of any sort and I cant use and media files. All I can do is semi browse the web and play solitare.
How can I fix this without having to reformat yet again? Also what could be causing this? I did virus scans and they come up neg, get rid of spyware and all that and it still happens. Only one Svchost.exe process is doing this, the others are fine.

[6z-8-z=4(z+10)]

what kind of services are you running?
start>run>services.msc

do you see anything suspicious running in there? if so im sorry!

[Unknown_Sniper]

everything looks like it should be running. nothing funky in there.

[Mr.Buttocks]

Smells like Sasser. *sniff* *sniff* Get that McAfee stinger thing and run it.

[6z-8-z=4(z+10)]

mind posting a screenshot of your running processes?

[Unknown_Sniper]

I highlighted the problem one in red and then the system idle process which is reading 00%

[url=http://img47.exs.cx/my.php?loc=img47&image=processes4lh.jpg:19873][img]http://img47.exs.cx/img47/916/processes4lh.th.jpg[/img][/url:19873]

[Sniper101]

here are some links to help out
About svchost
[url:abf67]http://support.microsoft.com/default.aspx?scid=kb;EN-US;250320[/url:abf67]
Viruses

[url:abf67]http://securityresponse.symantec.com/avcenter/venc/data/backdoor.xts.html[/url:abf67]