I am getting an error similar to this when I try to watch dvd's. Every program has a similar version of this.
unable to open the MRL 'dvd:///dev/dvd'
For VLC I have found a way to fix it.
CD/DVD Drive not working VLC error (SOLVED) (Page 1) - Help & Support (Stable) - CrunchBang Linux Forums
Problems Playing DVD Video in VLC - FedoraForum.org
Is there a way to make these changes permanent in all of your media player programs? I really don't want to have to figure this out for every media player program I have.