I'm in the Firefox camp:
https://www.mozilla.org/en-GB/firefox/new/
However, if you're getting the IE message that a website has been blocked, it might be worth checking that the date is correctly set on your computer. If it's not, the security certificates issued by some sites might be seen as invalid, resulting in you seeing that message. (To check the date, simply hover your cursor over the clock at the bottom right of your screen. If it's incorrect, right-click there and select 'Adjust Date/Time')