Another vote for FireFox here...I've been using it on all my computers for about five years now, and find many of its addons (AdBlock Plus, Video DownloadHelper, Flagfox, etc) very practical.
Chrome is a great browser as well, given its better use of memory and usefulness whenever FireFox crashes and demands an OS reboot.
Other browsers:
Safari - a bit too slow for my taste
Opera - for those very few situations where the other browsers won't run certain web scripts properly (but that's a problem with the website at hand...damn web designers and their "need" for IE compatibility!😡)
IE - wait, what? 😕