tungsten and DVD316 are onto the right stuff!
For months, I had a ton of things I couldn't get rid of and finally had a tech come in. He deleted several of the pop-up/adware blockers that I had tried and told me that many of them actually installed their own software.
In the end, I was left w/ Norton, Spybot Search & Destroy, and CWShredder... an my computer hasn't been better since the day I bought it
Some of the sponsors in our network have tours that send you into pop-up hell, and I would get so annoyed at the downtime they would cause me... not to mention the fact that ads for porn sites would pop up at inconvenient moments.
I'm very happy w/ the current set up!!