What to do with my Forum

My suggestions:
A Custom Skin- nothing too fancy, but enough for the average surfer to understand you took pride in your site/forum. This goes along way.
Free PHPbb board?- Calls in the army of backlink spammers if you had PR.
PageRank 0/10- Guess what you need to do?

The forum can easily pickup mainstream sponsors, but you might hit up Will76 for his cam promotion going on. My suggestion is to start working BL's with solid keyphrases. Id suggest you get Market Samurai for the "basic" understanding of keyword/keyphrases if you're a beginner.

Finally, the best tip I would highly suggest is to spend every waking moment getting solid backlinks. Why?.. because most new forum/blog/sites upgrades now have nofollow by default. In short, this means he/she who has the most high-PR backlinks in the near future wins.