I second that, Geoff. Firefox is free, easy to use, better at keeping out unwanted intruders, and will co-exist quite peacefully in your puter with IE. It also lets you selectively (or otherwise) delete cookies, something that I notice is now much harder to do with IE. I can't think of one reason NOT to switch (their email programme Thunderbird is good, too).

http://www.mozilla.com/en-US/