I've read through the other posts on this topic but my issue is a little different. I can see the disk in Disks and Files, I successfully downloaded VLC and I did the whole libdvd install and reconfigure and I installed the ubuntu-restricted-extras, and it's definitely a DVD not a BluRay.
But when I open VLC and try to open the disk, I can hear the disk turning in the external player and the screen shows the name of the disk (in this case it's JERSEY_SHORE_S1_D1 lol) and then it stops playing.
I'm just trying to enjoy my DVD collection on my desktop and any help would be greatly appreciated.
How old is the external player? Sadly DVD players don't last forever. I had an external DVD-RW optical drive from 2009 and last year it died so I had to purchase a replacement.
Have you ever cleaned the optical lens with one of these?: