just go through you're internet options under tools and just reset everything back to defult.. btw Mozilla is crap.. and Oprea well Oprea can't even view layers correctly.. IE is the best option to see all pages correctly.
Ofcourse M$ sucks but IE is the most accepted web browser on the net, hence 99.9% of all pages on the internet work with IE can you say that about Oprea and Mozilla... I think not

If want no pop ups in IE.. d/l the new beta google toolbar it works like a champ.