Helping a friend with computer running XP SP2 that has become slow. Slow to do everything, startup, shutdown and just about everything else. I can find no problems except when shutting down the computer shows a message about "Updating 1 of 3" and so on until update 3 completes and the thing shuts down. It takes about ten minutes to complete the updates. Every time the computer is shutdown it goes through this updating process.
Anyone experienced anything like this or can suggest a solution?

Have you run thru the MSCONFIG startup list, scanned for spyware & viruses?

I have not run msconfig but I did look at the tweakui list of things loaded up. The TweakUI scan found about fifteen items but I have no idea which ones are necessary and which ones can be deleted.
I did run an AVG virus scan and it found nothing. AdAware and Spybot S&D were run but they found very little. I also ran CCCleaner to empty the stuff that builds up with Windows.
Not sure what to do now. Thanks