Comment 48 for bug 44233

I'm using 10.04 Lucid; other ubuntu versions are probably similar.
The temp fix may or may not work for all udf types.

The bug seems to be caused by auto-mount.
Auto-mount tries to mount udf dvd as type udf.
However, udf dvd-video should be mounted as type iso9660.

A temp fix is to manually mount the dvd drive.

1. Make a new folder to use as a mount point, or use any existing empty folder.
  sudo mkdir /media/dvd1

2. List your dvd drives with this command:
  wodim --devices

3. Look for "dev=".
  Your dvd drive is likely to be /dev/scd0
  The shortcut /dev/dvd may also work.

4. Unmount the folder, just in case.
  sudo umount /media/dvd1

5. Mount dvd drive.
  sudo mount -t iso9660 /dev/dvd /media/dvd1

or if your device is /dev/scd0
  sudo mount -t iso9660 /dev/scd0 /media/dvd1

If you use vlc media player to play udf dvd-video, you may need to disable "DVD menus".
In vlc, Media > Open Disc > check "No DVD menus"
  Disc device = /media/dvd1

vlc command line:
vlc dvdsimple:///media/dvd1

All commands used listed:
---------------------------
sudo mkdir /media/dvd1
wodim --devices
sudo umount /media/dvd1
sudo mount -t iso9660 /dev/dvd /media/dvd1
vlc dvdsimple:///media/dvd1

If you are mounting an udf iso, try
  sudo mount -t iso9660 -o loop /pathToIso/filename.iso /media/dvd1