Hang on.... someone hijacked me once, and I think my brother Ramius walked me back out of it.... I just don't know if he is around.
ecurbh? - are you around and able to help?
Just on my way out the door...
I would reccommend using AdAware (
http://www.lavasoft.de/software/adaware/) to scan your system and remove whatever was installed to cause this.
I also cannot reccommend Mozilla highly enough - been using it almost exclusively for over a year now, and have yet to get an unrequested popup window.