Top Web Hosts Providing Forum
If you’re going to create a forum site at your own domain without any forced ads, you need a web host providing forum tools (phpbb or vbulletin).
Take a look at:
http://www.threehosts.com/forum
There you can reach the three reputable companies that are leaders in the forum web hosting industry. They fulfill all your requirements to set up your own forum.
Hope this helps.