Any player (vlc, movieplayer etc.) shuts down, can`t play

[thorinator]

Well, it took me two days to find this forum and hopefully an end to the problems. I am running Hardy Heron server ltd 8.04, I think this computer is amd64? (how to check..). After I installed Hardy (as a first time linux user and total noob lol) I didn`t have any sound etc, but after almost 3 weeks of asking questions and taking advice (lots of terminal work) everything was great. Then suddenly, after clicking on the updates notification (wish I hadn`t) for both Firefox and Hardy, any player (rhythmbox for mp3s, movieplayer, or vls for videos, open for a split second when I try to play a file from my computer, like .avi or .mp3, then shut. And sometimes it shuts the firefox browser window too, especially if I`m trying to play youtube or something. I have asked for help on another forum, and they`re great there, have helped a lot in the past. I just can`t seem to get help with this, and anything I`ve googled and read and done, does not help. If I cannot fix this, I will have to not use ubuntu and I really really don`t want to go back to windows. I need to view my web design videos though, as I`m learning.
I would really really appreciate any help here, thanks very much.

[arochester]

1) Make sure you have installed ubuntu-restricted-extras

2) Make sure you have installed the Medibuntu Repository and that you have have particularly libdvdcss2 and win32codecs or win64codecs. Instructions for installing Medibuntu are here: https://help.ubuntu.com/community/Medibuntu

Note that it is a 2 part installation (a) adding the repository and (b) getting the GPG key by inputting stuff to a terminal.

[thorinator]

Thank you arochester for your quick reply. I did as you suggested (but have done that about 3 times prior, and been to the Medibuntu community a few times, also I have installed the restricted-extras, a few times So I` wondering if something else is going on here and if I should do a clean install of Ubuntu, maybe try 8.10 this time (although I`ve read lots of posts complaining of bugs with it). I`ve just put this at the terminal:
sudo apt-get update && sudo apt-get install medibuntu-keyring && sudo apt-get
update (the GPG key). Was there something else I must do? thank you

Just tried to play an .avi in moviplayer, and vlc, same thing happened (also, an mp3 in rhythmbox )
I`m wondering if it`s a firefox thing, because my browser has been acting really buggy as well, like it keeps shutting down, even when I am on this forum, and when I was doing a Facebook `chat` with my nephew. stuff like that, grrrrrr!