Chips…
This may not be the sites you visited doing the pops….I had the every 10 mins thing happen to me a while back…and the cwshredder link a few posts above may be the solution.
Basically a few years ago vulnerabilities were discovered for resetting the homepage, adding links to favs, spawning pops. These have been re-exploited and are far more agressive and the latest xp updates should take care of this, AFTER you resolve the problem.
I have just gone through a format and complete reinstall with all the headaches that entails. Will be a week before my pc is back to what it should be. I would not wish that headache on anyone. I didn’t lose any data when my system finally decided it had had enough. Lucky me.