HELP what kind of Virus or scam is this?10 POINTS?

I have pop Ups ( bad ones) that do not let me get into internet websites they are poping up all the time, it drives me crazy, I already tried it by goin to REGEDIT and deleting some core sys files and also tried different virus and spyware scanns and have a Symantec AV which is the newest version, but still get those pop ups ( with naked girls). How to get rid of them?