My two favorites are phpBB and YaBBSe. Both are similar and written in PHP and use mySQL. Both are also freeware. You can also check out vBulletin, you have to pay for it and it's not much different than the two free ones.

www.yabb.info
www.phpbb.com
www.vbulletin.com




>Any recommendations for a forum software?
>
>I'm looking for easy setup and basic discussion functionality.
>
>Thanks,