kengr

So, is there a setting that tells XP to get rid of old temp files and the like?

Format C:, of course.

Then install some flavor of Linux, or if you MUST, Win2k.

(sorry, I know, cheap shot)

Norton, according to a number of sources, is far down the list now in good AV programs. Time was it was the best, but now apparently it's about middling level.