Windows XP Service Pack 2 - explorer.exe

OK... so after upgrading to Service Pack 2, explorer.exe suddenly feels it's cool to constantly hold my processor usage at various values between 2% and 6%. This is extremely irritating, to say the least. Over time, it makes my laptop hot... which, pardon the pun, is not cool. :cry:

I have:
Windows XP Home
Pentium III 1.0 GHz processor
256 MB RAM
5 gigs free on a 30 GB HD.

Can't think of anything else relevent... it didn't do this before upgrading to Service Pack 2.

Any ideas ? I've searched the Internet but can't find anything other than the realization it may not have been my most brilliant moment to upgrade to Service Pack 2, although I do like some of its "features..."

I had a similar prob but with VS.NET .... sometimes when I change from one project to another it eats the procesor, and locks up -- the rest of the PC is fine. Tunred out it was my virus scanner.... SP2 did something that casue the scanner to go nutz when perfomring some actions.