Urgent Help Needed

I was using my PC as normal, when suddenly my computer restared!! this happened right now!!
The memory wasnt being heavily used or anything. it just restarted.

once windows started up, I got this error message;
http://img365.imageshack.us/img365/7479/untitled6pz.th.jpg

I clicked on send error message, and then this page came up;
http://oca.microsoft.com/en/response.aspx?SGD=914db501-0bd2-45f0-aa19-aac198d8e867&SID=79

It says maybe a recent hardware or software change caused this.
But I haven't had any hardware change, and the most recent thing I installed was iTunes 6

I'm on windows Xp pro, SP Beta. After posting this message I will do a thorough spyware and virus scan

 

SP Beta ?

 

yep, SP2 beta. maybe its that

I did a spyware check, and removed all of the spyware, and did a virus check, and nothing there

I'll try the full SP2 now