I recently built a PC solely for the purpose of
using it as a HTPC, constantly hooked to TV, for playback of MKV's , XVID's and eventually Blu-ray Discs.
Now I could put into Windows, and fire up VLC and play videos that way, but thats a little cumbersome, and not exactly user friendly ( read: girl friend friendly) .
Xbox Media Center, recently was released for Windows,
http://xbmc.org/
I figure, I'd bring back memories of the days of the Xbox, when I used to use XBMC for Divx files
. I originally had Catalyst 8.8's and found playback stuttering. Got the 8.9's and everything works pretty good ( still early in dev.) Can play MKV's Xvid's everything I threw at it , so far, and its a user friendly menu.
Any one use any Media Centre's or similar programs. Linux MCE looked interesting but Hardware compatibility kind of turned me off.