Just today i was bit searching for some free forum sites, i found a very old free forum website, which is worth and advanced forum for your site. And the most important thing is you just have loads of mods installed for your site, its just one-click install. Website link is http://jfb.jcink.com its worth trying, if you need any help, just shout at me here and i will try to help as quick as possible, once i come online.