[theFM]

See really there is no mod in this world will make guests look at to your forum
But you can try these stuff : -

1. Get your Forum Unique, even if not better but make it unique
2. be proper in general, and make your forum to the point , don't include off-topic sections or forums
3. get unique content , be the first to get the content
4. Do not try to copy other forums or give them new features just because your competitors have them installed
5. Create a New Design for your forum.
6. get seo content , vbseo and sitemap will help you in that

any forum software can be good lol
even the most big forums are of phpbb , so software does not matter

the thing which matters is how you manage it !!!