Had DVD playback issues after installing Mint 11, this was what was going on and some background. I'm a noob but not totally.
Had installed Mint 12 on a Dell D830 in a dual boot Vista config. to get away from Vista.
Installation was fine but 12 was very uncomfortable to me.
Installed 11 in its place from the DVD iso version. After the installation I had no DVD playback, media would be recognised but the media players would error "not responding". Embeded media ie Youtube etc would play fine. DVD drive would play CD audio & obviously installed the OS so the drive seemed OK.
After updating packages and no luck on forum searches to get an answer I found this after multiple google search strings.
It seems like the Mint 11 install had somehow corrupted or changed my DVD region setting.
Downloaded & installed regionset and found that my DVD drive came back with no region set. Reset the region to 1 North America. & the drive now plays DVDs
Posted this to maybe offer help to someone else and ask if anybody has any idea on what the hell happened and why?