oops, i think i posted in the wrong section...
i don't like vista.. xp for me
Optical drives, whether DVD or CD-RW are now among the most unreliable computer components for long time use.
The problem you describe is typical of a drive that has been used so much that it is worn out. If under warranty, the company will send you another free that will last to the end of your warranty.
if already out of warranty, it is time to buy a replacement.