just creaet a symlink from cdrom2 to dvd, it'll make things a lot easier, as /dev/dvd will be used by many programs as a default
ln -s /dev/cdrom2 /dev/dvd
and what kind of files are you trying to play? there are many xine plugins at the Penguin Liberation Front, search for it.
of course, the better solution would be.... MPLAYER!!!!!!