The single best media player for your computer, VLC, just hit version 1.0 today.
If you have ever had trouble playing media on the web, this is the one for you. It plays everything. I’ve never hit anything it can’t play. Also, it takes up waaaay fewer resources on the computer. It does not load a ton of extras like Apples awful Quicktime and MS Media player.
See a longer article about it at Cnet. Ans download it her: VideoLAN – Download from mirror
As a techno-guru, I can vouch for this. I have been using VLC from the early beta days, and it just gets better.
I load it on all computers, Windows, Mac, Linux, that I come across, as a substitute to whatever is canned with the system, and it ALWAYS works better.
No codecs to download, no proprietary software, just Open Source goodness!