*Can I copy A DVD to the computer?*
Youm mean from a DVD of the type that goes with your telly, across to a computer - only if you have a video capture card in your system, otherwise ther'll be nowhere to feed the signal into.
Don't you already have a DVD player in the computer - if not they're very inexpensive - if you have, then just use that.
What's all this got to do with posting a DVD? - methinks you're not telling us exactly what you want to do.