viron is right. the only way to get it working on all distros is to compile it from source. what did not work when you tried it? i don't understand it. i can give you a short guide:
1. go to http://www.mplayerhq.hu/design7/dload.html
and download the source code.
2. after you did so you should have a file called MPlayer-1.0rc2.tar.bz2 in your download directory. unpack it with ($ is the user prompt):
$ tar xvjf MPlayer-1.0rc2.tar.bz2
by now you should have a directory called MPlayer-1.0rc2/
3. go to http://www.mplayerhq.hu/MPlayer/releases/codecs/
and download all-20061022.tar.bz2
4. unpack all-20061022.tar.bz2 with
$ tar xvjf all-20061022.tar.bz2
by now you should have an additional directory called all-20061022/
5. create a codecs directory. it actually doesn't matter where you create it just remember the location. you can do this for example in /usr/local/lib or /usr/lib like this:
# mkdir /usr/local/lib/codecs
if you get permission denied errors change to root (recognize the '#'? this means do the following command as root. if you change to root you'll see that your prompt changed and displays a '#' at the end).
6. now copy all the codecs from the all-20061022/ directory in /usr/local/lib/codecs (or /usr/lib/codecs respectivly). let's say all-20061022/ is in ~/tmp then you have to type:
# cp ~/tmp/all-20061022/* /usr/local/lib/codecs/
7. configure mplayer. let's say MPlayer-1.0rc2/ is also in ~/tmp than do:
$ cd ~/tmp/MPlayer-1.0rc2/
$ ./configure --codecsdir="/usr/local/lib/codecs"
if you get error messages at this point you are likely missing something. give the output.
8. compile mplayer:
if you encounter errors here you are seriously in trouble. this is very unlikely however. still give the output
9. install mplayer:
you shouldn't get any errors here. for permission denied errors remember the '#'. you need to be root!
10. you did it!
to play a file just type:
$ mplayer <FileYouWantToPlay>
11. further info either here or do
good luck, vadkutya