Apple TV vs. Mini vs, Sonos

I've been reading these forums for a couple weeks trying to figure out the best way to organize a large CD collection (2000 CD's) and to access it wirelessly on two systems. Having a friendly interface for the other family members is important.

At first I was leaning toward a Sonos solution with a NAS attached. Then, I replaced my old IMac with a new one and really like the Front Row feature. I also have an Apple Wi-Fi using Airpport Extreme (the older 801b/g version). Having Front Row available to manage my iTunes library via the video seems like a better solution than Sonos.

He're my questions:

I read that Apple TV won't support web radio. I usually tune in a channel and open it with ITunes, drag it to a Playlist and name it. Whenever I want to listen to it, it's in a playlist. Front Row accesses these easily on the new IMac. I assume they work the same way with Apple TV. Also works for stations accessed through Live365.com, which gives you 10,000 stations to choose from.

I'm not clear why Apple TV has the built in hard drive. Does your ITunes content have to be on the Apple TV drive or can you access your library stored at another location wirelessly, such as a NAS, via Front Row and the Apple TV?

It seems to me that the simplest solution is to use a NAS to store my collection and add an Apple TV to each system, accessing the library via Wi-Fi and connecting the audio via Toslink to a DAC and the video via composite video. Is there a flaw in my thinking? Is there an advantage to using a mini? There's no place in either installation for another screen.

Any suggestions would be appreciated.