Well anyone can replace or clean a laser in a dvd drive :p The past two xbox's I fixed and resold were simply just old samsung dvd drives and the rubber band for the gears got stretched out. Throw it in some boiling water and tadah, its good as new
Gotta love turning $40 into $100 with some boiling water. If your box is having any kind of trouble like that though I'd definitely suggest cleaning the lens, or even adjusting the dvd pot if you still have problems, should extend the dvd drive's life for a good bit longer most of the time.