Multimedia – How to Play VOB Files from a DVD Disc

That title has structure protection & is the likely cause of your problem with playback. The protection isn't an issue with the latest couple of libdvdnav4 releases but it appears it is with the version provided in lucid.

Assuming your drive is /dev/dvd, if unsure you could run this & check the /dev/ links

sudo lshw -C disk

Look for the section *-cdrom, if it shows /dev/dvd then use below command, if it says /dev/dvd1 then adjust, you could also use the /dev/srX instead where X is usually 0 or 1

If you are in region 1 then the main movie is title 24 so this may work, -

vlc dvdsimple:///dev/dvd@24 

command means - dvdsimple:// (no menus), /dev/dvd (device), @ title number

(starting in vlc-1.2 the @ is now a #)

Otherwise it's quite possible you can upgrade libdvdnav4 & libdvdread4 to newer versions, there are no real dependency issues. I don't have a lucid install to d. check but shouldn't be an issue.

If so you need to upgrade both packages at the same time, I'd use the 11.10 packages. If you wish to let me know, I'll edit in how.

EDIT: - realized I had a lucid iso so did a quick boot to live session to check out. You may not be able to play Thor with the above method though it could be handy for some other structure protected disks. I went ahead & upgraded the libdvdread/nav libs & you should then have no issue with Thor.

In some cases even with the newer libs you may have to resort to playing by going directly to the main movie title, Cars2 is an example of that, Thor should be fine as normal

To upgrade 10.04 to newer libdvdread/nav

Will use the 11.10 packages, one could use the 12.04 though 11.10 will suffice.

Open a terminal, run this command, then leave the terminal open

sudo apt-get remove libdvdread-dev; mkdir dvd_fix; cd dvd_fix

Then go to these pages, pick your arch, right click on the top listed mirror > save link as, save into dvd_fix folder (it's in your home dir.

http://packages.ubuntu.com/km/oneiric-updates/libdvdread4

http://packages.ubuntu.com/km/oneiric/libdvdnav4

Once both packages are downloaded & in the dvd_fix folder run this in the still open terminal

sudo dpkg -i *.deb

that will upgrade you & disk should play

If you need or think you may need the libdvdread/nav dev files for building related sources

We'll do this way to avoid possible broken packages - do AFTER the above is done

In your dvd_fix folder create a new folder named devs

Go to these 2 pages & download the -dev packages to the dvd_fix/devs folder like before

http://packages.ubuntu.com/oneiric-updates/libdvdread-dev

http://packages.ubuntu.com/oneiric/libdvdnav-dev

When or if you need the dev packages installed then just open that folder, right click on libdvdread-dev & install with gdebi. Then do the same for libdvdnav-dev, do libdvdread-dev first

sudo apt install libvdpau-va-gl1

Then change with sudo nano /etc/X11/Xsession.d/20vdpau-va-gl

remove any # in following block

[ ! -f /usr/lib/$(arch)-$(uname -s | tr '[A-Z]' '[a-z]')-gnu/vdpau/libvdpau_va_gl.so.1 ] || \
   export VDPAU_DRIVER=va_gl

This enables libvdpau-va-gl as the default VDPAU driver.

Reboot.

sudo -H gedit /etc/X11/Xsession.d/20vdpau-va-gl

remove means delete them.