svchost and unusual CPU usage

For the past month now, I've noticed after a while of being on Windows, my games would start getting jerky. I had no idea until just recently what was causing it, but how I have. In the task manager, I spot several svchosts running, which is apparently normal, but one of them seems to be hogging my CPU, even though it's not really taking too much a toll on memory usage. My CPU usage just steadily increases until I close it, then it goes back to really low numbers, but the svchost will respawn. The one I close is marked as as LOCAL SERVICE, while the rest are SYSTEM and one is NETWORK SERVICE. It seems only the LOCAL one is the problem. What can I do to stop this from blasting my CPU all the time?

I'm on XP and I've recently upgraded to SP1.