My favorite browser is Mozilla, especially with the added preferences bar.
With the preferences bar, instead of going into the program's preferences the user with one cllck can turn a website's colors on and off (Ars Technica drives me crazy), cookies, images, the disk cache, it's history, referral pages and a bunch of others, including Flash, although I use AppleScripts to turn Shockwave/Flash on and off. The bar also allows the user to spoof browser identites, including the Great Satan's running on Mac or Windblows.
But the main reason I use Mozilla is because of it's ad-blocking ability. As well as popups, it will block forever any ad you want it to (Firefox, which is another branch of Mozilla, does this, too, but I also use Mozilla's email program because running both means running only the one app), and Mozilla's spam filters and ability to redirect mail work well -- and Mozilla has more preferences controls.
I visit the same 20 to 25 websites two or three times a day, and each is ad-free, as is any new site I decree should be, which is all of them.
Occasionaly I have to boot into OS 9, and because Mozilla's preferences files in Systems 9 and 10 are identical, it's simple to keep my bookmarks (about 400) and email files current with each other by using aliases and file-dragging AppleScripts.
I've tried 'em all, but in my opinion, Mozilla is the best at uncomplicating life.