One of the things Ive been looking for is a good user interface for my HTPC. Right now it's pure geek and the WAF is quite low. She does OK with the music side of things, I use WinAmp with a bunch of tweaks for audio quality and she is learning her way around that.
For movies and TV shows it's another matter. I primarily use VLC for all video files as it has the best rendering I've seen yet but not a very user friendly interface.
I also stream video from the net from various TV stations and other sources and those are all web based so we access that through "favorites" setup in FireFox
I've been looking for an all in one that's not owned by Mr. Gates as WMC is.
I've tried JRiver, pretty good, as well as Boxee, not my cup of tea.
Yesterday I installed XBMC http://xbmc.org/ and for you Apple geeks its going to really open your eyes as to what AppleTV can do.
I'm currently running it on my HTPC with XPPro as the OS. I will be switching to Win7 soon and it will run on that OS as well as Linux.
So far it's the best I've used and the wife likes it too and that's after one evening of use.
The install is quick and simple, it works great with a dual monitor setup like I have and it has a lot of plugins and scripts to extend it's functionality.