Personally I always used firefox. But recently I have turned to Explore 7.0 as it has all the stuff firefox has that I need for my uses. So either of these 2 I believe are the best browsers.
I use Firefox or Opera. I prefer Firefox for some reason even though it tends to kill my memory once in awhile. I've heard a lot of good things about Safari although I've never used it...gonna have to download it to try it out now that I see so many people have listed it.