Guess opinions differ, from experience and various other sources I've learnt that phpBB 2 is instable and lacks a lot of useful features
. Your experiences might be different though, or they might have upgraded it, can't say...
vBulletin remains the king though. I've recently purchased it for use on my own website, and don't regret it at all... so many features, so customizable, you'll find new admin options weeks after installing it
.
As for converting, vBulletin itself offers this functionality, once you've registered you can get 'em from the members area:
Quote:We currently offer a set of scripts that will allow you to import posts, threads and users from the following programs: Infopop Ultimate Bulletin Board 5, Infopop Ultimate Bulletin Board 6.0, 6.1 and 6.2, Infopop UBBThreads 5.4 (formerly wwwthreads), vBulletin Lite, Infopop OpenTopic/UBB.x, Ikonboard 2, Ikonboard 3, phpBB2, DC Forum, XMB, and ezboard (posts only, not members for ezboard).