The only other conversion you will need is SUPER codec. Which can convert anything to anything, but is a bit mind-bogglingly feature rich for daily use.
I'm definately gonna side with Slug, SUPER is one of the best programs out there. Once you learn how to use it, you will be able to effectively convert anything you want to any type of file. There must be 25-or-so different formats it's compatable with. Click here for a link.
