Do you have modifications added? Maybe one of them doesn't work with the latest PHP 5.2.1. If that's the case, go to your DreamHost Control Panel and change your PHP version to the 4.x variety and see if that fixes anything.
Also feel free to try my message board and see if anything there doesn't work. I just migrated the board at http://techbroadcasting.com/forums to MyBB with a beta SMF converter, and it seems it came through in decent fashion, and all the stuff is intact (though I had to do a little trickery because of conversion artifacts).
Co-Host, The Paracast
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