I've never paid for a forum before, but I guess it's the same way.
If you paid $160 for it, hopefully there's a read me...
Login to DreamPanel (a.k.a. DreamHostControlPanel)
Click Goodies -> MySQL
DB Name: anything, I recomend something like firstpartofdomain_vb
DB Hostname: This is what you enter for the host (it won't be localhost, it will be something.yourdomain.com) I would recomend calling it what the forum is something like vb.yourdomain.com
DB Username: something easy to remember, posibly same as the database?
DB Password & Repeat Password: whatever you feel like.
Then upload all the files your told to upload.
Then go to the install.php file.
Fill out what you put, and remember there's no such thing as localhost.
If it tells you to run a query in phpMyAdmin, go to whateveryouputforhostname.yoururl.com and login. Then select the database and run the query...
Hope this helps
I don't know anything else about vB... I think it's too explensive compared to phpBB or PunBB or TMB or...