Upload the vbulletin.sql file to an accessible place on your server.
Install the latest version of vBulletin (2.2.8 as of this post) as a fresh install on a clean database.
Import the vbulletin.sql file, and then run the upgrade scripts from whatever version you were running (refer to the vBulletin Manual in the Member's Area for which upgrade scripts you need to run).
Hope this helps!
Radon3k.