Software OR Hardware

I have a Lite on dvdrw shw 1635S
Just recently it stopped working.
I have tried everything I can think of when it comes to the software part. Meaning, I have un-installed and re-installed the drivers.
I tried downloading and updating the firmware but I get an error stating that no matching drive detected! And that it is intended for the Lite On model I have installed. Weird that it doesn't see that DVD drive that Windows says is installed and working properly.
Also, when I try and burn a dvd using either Shrink or Nero, the burn process goes all the way to the very part where it prompts me for a blank disc, I put one in the tray and then it doesn't see it; it just keeps on looking. So, what do you think could be the problem? Is my drive shot? Oh, I also tried doing a Roxio Zapp, which seemed to have operated fine, but didn't fix the problem.
thanks ,
frustrated