Does the Drive even recognize disks? ex: if you put in an install disk, can you actually install it?
If it does skip the following
You could try inserting a bootable disk and see if the computer will recognize it even if windows does not. (make sure CD is set to boot in the bios, and that you can actually see the CD drive in the bios.)
If that doesn't work it is most likely
hardware (it could still be software, but if it isn't recognized it usually is hard ware.
Make sure all the cables are plugged in tight and that the jumpers are set in the right configuration.
When it's none of the above it is generally a bad drive or bad I/O configuration.
If the DVD drive is recognized and just not writing it is probably a software error.
What O/S are you running, if it is XP that might be why you cannot copy and paste onto it. I would first try some free burning software to see if it can even burn anymore. like http://www.cdburnerxp.se/download.php
If you get any results just post what you can and can't do.
If any of this doesn't make sense too you please tell me and I will elaborate.