Dont. Just move to a better browser (such as Mozilla, Opera, or Mozilla Firebird). All of these block pop-ups, and better than any third party software I have seen.
If you are still getting popups, for example when you arent browsing, it is likely some spyware on your machine. Download AdAware (<a href="http://www.lavasoft.de">LINK</a>) and run it, it will clean that up.