Ok, somehow our server exploaded and we need to change. I have a backup of our forums, but it is an sql file. What am I supposed to do with that?
phpMyAdmin > Forum table(left side) > SQL(right side)
Open the .sql file, and copy all of the contents, then paste them into the box, and click "Go"
Also you can import the SQL file, click the import tab in the top navigation, but Tom's method would be better because if you have a big forum when importing that backup it might timeout every time you try.