DVD drives spin up the platter and attempt to read from it. If the read fails, they stop spinning the drive. So, I think the problem you have is that the device won't read.
DVD drives have some very small plastic pieces that can break and cause failure. They also have a read head that can get out of alignment.
If you're ambitious, look at the drive and see if you can find any other damage. Don't run the drive open, though, because there is invisible laser that can blind you (there should have been a warning on the top of the drive when you opened it).
I checked eBay and this DVD player sells for under $20 (including shipping), so don't spend too much time on it.
Definitely let me know if you have questions or comments.