Which free Firewall is the best as of today ?

Question

Would it be in conflict with Internet Explorer 6/7, Mozilla Firefox 2 or Opera 9 ?

Answer 1

I feel the best free firewall is Comodo.

The only firewall that doesn't leak
Unfortunately, most firewalls leak. But Comodo's Firewall is unique in that it passes all known leak tests to ensure the integrity of data entering and exiting your system. Comodo has put firewall through all kinds of sophisticated tests to ensure its firewall powerful enough to ward off these attacks with default settings. No other firewall has had to work this hard. Take this test yourself.

http://www.personalfirewall.comodo.com/

Answer 2

Zonelabs ZoneAlarm is the best firewall right now. It works well with all browsers.

Answer 3

just use windows firewall with xp sp2
works with ie/firefox
if doesn't work with opera then add it as an exception