I have had several DVD which display as empty in a computer but in a DVD they play?how can I play such dvds I a computer?were they written badly or is there a program that can be used so that you can access and see the movies?
Secondly,how can I watch a movie without it hanging?I have had several DVD which play well in a dvd player but when they are in a computer the pictures sometimes freeze/hangs?Is there a program I can use to do this?

You are missing the codecs to play the DVD's. Do you have a dvd rom or is it just a CD rom. If it's not a dvd rom you can't play it on the computer.

Try downloading some dvd codecs that will solve your problem instantly.

How much hard drive disk do you have free as well may give you the poor playback as well. Try cleaning up all unnecessary files on the disk.