Curious about svchost.exe

Recently this computer has been acting a little odd. Not quite anything wrong with it, just a little jittery with certain apps. Whenever I noticed this, I checked the task manager to see what processes were eating up CPU and to my suprise it was often svchost.exe, listed as a local service, taking up about 20-30% of an amd3700+. I find this to be odd to say the least. Killing it doesn't make XP want to restart.

Now, let me tell you a little story. A few days ago I stupidly clicked on a link that someone (I knew them - turns out they had been given a trojan or something which was using AIM to distribute this link) had sent me. They say they got it through visiting the link with IE. Thankfully this machine has a fully updated Firefox. When I visited the link, the window bounced around the screen (think "You are an idiot, ha, ha, ha, etc etc." if anyone remembers that website) and attempting to launch various applications including Outlook. Obviously I denied all of these launch requests, and got tired of the whole thing and just reset the box. AVG found nothing, tried a couple of random spyware and adware removal apps from download.com, they found nothing either. I'm not particularly worried, but I'm also not satisfied with my own investigation, so I'm curious if any of you have any input. Do you think I'm in any danger? Nothing fishy is going in except for that svchost instance taking up more CPU than I think it should.

Anyhow, let me know what y'all think. Thanks.