Check you /dev directory and see if there's a file called "dvd" in there. It doesn't look like there is. /dev/dvd is usually just a link to the true device file for the dvd drive. If it's missing you can make the link easily. Say your dvd drive is on hdc. To make the link, open a console, su to root and run:
# ln -s /dev/hdc /dev/dvd
Afterwards, try totem again and see if it works.