superantispyware is also a very good anti-malware utility and it can remove unwanted apps.
Revo uninstaller is also very good at detecting unwanted programs.
some websites have pop ups that open new tabs in your browser. Some AV programs can assist with profiling these sites and they can block them. I use AVAST Free, and I don't have many issues.
Torrent sites and "News" sites are common sites used with the pop ups.