All those file formats you mentioned are proprietary. Being completely free and open source, Fedora doesn't distribute out-of-the-box support for those file formats. Fortunately, there are folks who maintain third-party repositories with the naughty stuff so we can have our cake and eat it to.
Leigh's got you set up. To clarify, those commands will add Livna (a third-party repository) to your yum configuration, and the second command uses yum to install some "naughty" codecs from Livna for playing those proprietary media formats.
EDIT: you may also want to take a gander at this page
. It has lots of info on getting codecs working for a variety of media players. I'd also suggest trying VLC as your video/movie player - once you've enabled Livna, run yum install vlc
. It's a great player.