Do you know a good firewall?

Windows XP with SP2 has a good firewall, you could probably use it.Try McAfee's security center.I think its the best.

Yes I know! I use Comondo's personal fire wall because it is free. You can download it from their website: http://personalfirewall.comodo.com/ It works with Windows 2000 and XP (and probably Vista), if you have anything before Windows 2000, maybe you should Zone Alarm, have a nice day. Pablo

Zone Alarm offers a good and free firewall, and AVG offer a good free anti virus programme, so I hope this helps you out. As far as I know both offer a paid for version of each piece of software as well, so you'll probably get limited functionality with the free versions. Also if you are using Microsoft XP/Internet Explorer Service Pack 2 then there is a firewall installed already, just don't use more than one firewall because they may conflict with one another.