I also have this problem, on 13.10. It seemed that /dev/dvd did not exist, but my DVD device was available as /dev/sr0. A symlink fixed it:
sudo ln -s /dev/sr0 /dev/dvd
I guess this might only be temporary though (i.e. until I reboot).
It's worth noting that VLC played the DVD fine without the symlink.
I also have this problem, on 13.10. It seemed that /dev/dvd did not exist, but my DVD device was available as /dev/sr0. A symlink fixed it:
sudo ln -s /dev/sr0 /dev/dvd
I guess this might only be temporary though (i.e. until I reboot).
It's worth noting that VLC played the DVD fine without the symlink.