One area we've struggled with, and from what we've seen it's a problem for a lot of users as well, is media support. Linux doesn't natively allow playing encrypted DVDs (because of proprietary coding and moral dismay), though there's a fix. So here is a roundup of our picks for media players. Beside the name of the programs I have listed the repository package name for easy install through apt-get.
There are three great media players, almost all identical actually. I've always been a Winamp fan in Windows, and they make a version of Winamp 3 for Linux. These are three apparent Winamp clones, but all good players which I haven't had trouble with. Beep Media Player (beep-media-player), XMMS (xmms), and Audacious (audacious) are great programs and play mp1, mp2, mp3, Ogg Vorbis, wav, raw, and au file support.
Here is one category Jeremy and I disagree on, and it's only because he has had some compatibility issues on his laptop. I prefer KsCD (kscd) for its features and simplicity. It's a very clean program, and I like it for CDs. Jeremy prefers the Free Software Foundation's CD Player (gnome-media). I recommend trying them both and seeing which you like.
VLC Media Player (vlc) is great program with excellent DVD playback. It's also a full media player, though I prefer other programs for other media types, though if you like an all-in-one solution to your media playing needs I recommend VLC.
Most likely everyone who has used Linux, almost any distro, for a length of time is well aware of Gimp (gimp). Gimp is like Adobe Photoshop, but free. It's a wonderful photo editor and can save in a wide range of file formats. I recommend picking up the gimp-data-extras package as well for additional features, especially for the professional or semi-pro digital artist.