This is a little confusing. I opted to install Kubuntu  Feisty on my new Sony Vaio. Until now I’ve mostly been a Debian  user, but I’ve wanted to try Ubuntu or Kubuntu for some time now, since it has such a great reputation. So far the only problems I’ve had after installation have been that the system won’t come back up after Suspend, and that DVDs haven’t wanted to play properly.
Specifically for the DVD problem, I’ve been convinced that it’s a problem with libdvdcss2, or something closely related to it. I installed the latest version available (1.2.9) from Medibuntu  and had all kinds of problems. For example, Ogle would write console messages such as “WARNING[ogle_mpeg_ps]: Found a scrambled PES packet! (1)”.
Kaffeine would pop up dialog messages such as “The source seems encrypted, and can’t be read. Your DVD is probably crypted.” At the same time, I’d be able to use kaffeine’s right-click context menu to jump directly to specific bits of the DVD, even though using the DVD’s own menus to navigate would often cause the session to die. To me, this implies that it’s not something specifically to do with decrypting the disc encoding.
Strangely though, I seem to have been able to fix it by downgrading libdvdcss2 to version 1.2.5. I tried this after reading the Ubuntu Playing DVDs instructions  for Ubuntu Edgy (now out of date), which suggest running “sudo /usr/share/doc/libdvdread3/install-css.sh” from the libdvdread3 package. This script essentially downloads and installs version 1.2.5-1 of libdvdcss, and suddenly everything’s working. I tried re-installing 1.2.9 over the top of 1.2.5, but that breaks it again.
Anyway, I’ve placed a Hold flag on version 1.2.5 in my repository, to make sure it doesn’t get updated accidentally. I’ll be interested to find out one day if this is a libdvdcss2 bug, or if it’s something else that I’ve broken.