I don't know Apollon but, these are the basics.
To play a .mp3 you need to have a mp3 decoder installed. To rip an .mp3 from a CD you need a mp3 encoder installed. Lame is one of them. Install Lame for your distro.
To play .avi, .mpg, .wma, .wmv you will need windows media codecs installed. Read the help files and put them into the folder directed to.
To play real media files you need realplayers codecs, or you can try Helix player.
Realplayer10 works as good as Realplayer for winblows.
For the windows video install the codecs from your players site. Or Mplayer, which is considered by some to be one of the best streaming players for linux.
For example here is Mplayers site.