Opera is by far the best browser...too many reasons to list.
Here is an interesting read that gives you a rundown on its many features and in some cases how it compares to FF or IE.
http://operawiki.info/WhyOpera
If you are an IE user, or strictly an IE engine user, I'd recommend Maxthon. The best in the IE engine dept.
My opinions of FF are not very high at all. It's claims to be more secure are nothing staggering when compared to other browsers, besides IE, as long as you practice safe surfing. Any idiot can get hijacked using FF too. FF's most negative characteristic, however, is it's speed in rendering pages. Slow.
