Cannot mount DVD!?

[pg3bton]

Hi. I'm new to Linux but have VLC installed. I get the followinfg error:

libdvdnav: Using dvdnav version 0.1.10 from http://dvd.sf.net
libdvdread: Encrypted DVD support unavailable.
libdvdread: Could not open input: No medium found
libdvdread: Can't open /dev/scd0 for reading
libdvdnav: vm: faild to open/read the DVD
[00000293] dvdread demuxer error: DVDRead cannot open source: /dev/scd0
[00000296] access_file access error: cannot open file /dev/scd0 (No such device or address)
[00000291] main input error: no suitable access module for `dvd:///dev/scd0@1:1'[00000282] main playlist: nothing to play

I am running Yellow Dog 5.0 with e17 on PS3. Any help to this new foray into Linux will be greatly appreciated.

[pg3bton]

I have sorted the DVD encryption and this is now the message:

libdvdnav: Using dvdnav version 0.1.10 from http://dvd.sf.net
libdvdread: Using libdvdcss version 1.2.9 for DVD access
libdvdread: Could not open /dev/scd0 with libdvdcss.
libdvdread: Can't open /dev/scd0 for reading
libdvdnav: vm: faild to open/read the DVD
[00000293] dvdread demuxer error: DVDRead cannot open source: /dev/scd0
[00000296] access_file access error: cannot open file /dev/scd0 (No such device or address)
[00000291] main input error: no suitable access module for `dvd:///dev/scd0'
[00000282] main playlist: nothing to play