Windows Updater - causing screwy slowdown

Recently, at times, my IBM laptop running XP Pro slows down, almost
to a crawl. Doing a CTL ALT DEL and I look at the process running,
the Windows Updater is showing 5 or 6 of the thing running, doing
what I don't know, as I had just done an update manually the day
before.

I tried removing Windws Updater from the Start Menu,but when I went
to do a manual update, it said I must reactivate it to update.

Could a virus cause this weird behavior? How can I stop these
multiple update operations from starting in the first place?

I scanned the computer with Super Anti Spyware and AVG anti
virus is running in backgound all the time, and a few Trojans
and tracking cookies were found and removed.

Any suggestions appreciated. If I reboot, the computer seems to
go back to it's original speed.