Jonathan "c0mrade" James, famous for hacking into Pentagon and NASA computers at age 15 gave an interview with PC magazine and was asked about the most preventable security holes that he has seen. He said that un-patched software was at the top of the list, "and don’t use Internet Explorer".
IE is notorious for opening up computers for numerous browser based attacks. Looks like c0mrade knows all about them. IMHO, I’d say, use Firefox.