Chances are, unless you changed something, that this will have an easy fix.
Windows doesn't normally need drivers for optical drives like that, but you may want to check this with your suppliers. Also check that the internal cabling is correctly attached. (Be warned this invalidates your warrenty unless your a certifed profession or a member of a professional body dealing with electronics.)
Just said this osmewhere else as well, you may want to look into how difficult this problem is to fix and compare it with the £10/15 DVD burners you can now buy. Is it worth your time to fix the problem or would you like to get new drives?