First thing you should do is to download a spyware detector/cleaner. I recommend Spybot Search & Destroy. http://www.safer-networking.org/
It's free, too!
I'd be willing to bet you have a ton of spyware on your computer (too many porn sites visited ;-) ) that is causing the popups to be spawned . Since I started using a spyware detector the popups are gone. As soon as I get a popup or two that I don't like I run the Spybot again and they disappear. You will be surprised what you find on your computer! You may also be surprised at the tracking cookies that you will find.