Alright, Firefox basically is Open source, allowing people to edit the code, and thus it is much more secure. Also, this makes it have better features such as using less memory, and it is also much, much faster than Internet Explorer. If what you are going for is speed, and you have a considerable amount of space, You might like Safari, which is very slightly faster than Firefox. However, Firefox has addons and you can program it to your needs and specifications using Greasemonkey. So who reigns supreme? In my view, Firefox owns every other browser. Also, it won a guiness world record for most downloads in a day.
Firefox......
IE shows sgforums oddly when it is double posting while firefox shows the two post seamlessly
Use this post to compare, run IE and firefox to see my this two post, firefox is 100% better