You'll probably have best results with VLC and MPlayer and very seldomly need to use QuickTime player. Apple's DVD player is also nice if you ever need to use it.

At this time you're looking at having to use all these tools from the finder with a mouse and keyboard (or remote controlling the OS UI). Unfortunately there aren't any media front-ends available yet in a polished enough state to consider for full-time usage. But at least thyere are a few being developed that may eventually fit the bill.

I was considering the Mac Mini with an external HD to run as a music server and also to play media. Then I decided I'd really like to have a PVR again (right now) so I ended up building another PC. I'd much rather be running a Mac for this purpose because the video driver software and controls are better (and I can influence their development ) but alas, it's the lack of the third-party software that prevents this right now.

Bruno