I believe vBulletin is PHP + MySQL which we fully support. We offer a 30 day money back guarantee and will help you with anything needed to get the software up and running AND running fast and reliably for you. We love to help our customers with software they are trying to run, it gives us a better insight into what they are using, and allows us to find new ways to tune the servers to run it all better. We've done this with DotNetNuke, Wordpress, and Joomla with great success.
You may also be interested in Community Server, this runs without any issues on a GearHost ASPNET or higher account and does everything you are looking for with the vBulletin publishing suite. Blog, forums, etc.
http://telligent.com/products/telligent_community/