phpbb and ikonboard forum scripts

Hello, I am trying to decide between these two scripts and was wondering if anyone has either of them installed. The one thing I need that I can't figure out if either of them have is whether or not, I can hide categories (that contain the forums and topics) on the category page and based on a users log-in have them enabled. If that is not possible is it possible to create 2 category pages and store them in one database, (hosting company only allows one instance of a forum script to be installed) one for the forums that everyone that comes to my site can see and another category page that will actually only be available in the restricted members only page. If it helps, here are the links http://www.phpbb.com and http://www.ikonboard.com I think I prefer the phpbb forum because ikonboard uses cgi scripts, or it least that's what it looks like. Any help would be greatly appreciated. Thanks Indera