MadMonkey: Well McAfee seems to be working fine, it might be that they've just ironed out the bugs since you used it.

As I keep saying.. Combofix. It gives the registry a really deep scan and I've found it to have fixed various bugs thanks to ad's or the like. My PC's install disk had an old no longer in use (they've gone broke) free trial for security software. I removed from the installed progs list all entries related to it, but the ad to buy it kept coming up. Combofix listed all the registry entries and I could see where the damn prog was hiding that was causing the ad's.

Two minutes with Reg edit and they was gone.