1) I would suggest XLD to rip your CDs as I find it much more flexible than iTunes, and easier for embedding album information and artwork... Plus you have the possibility to choose the FLAC format which is not available in iTunes.
3) If you ever want to use a computer (Mac Mini) as the core of your music server, and wish to reach the best sound quality by using an external DAC, one option that is often disregarded by 'audiophiles' is to use audio interfaces used for music production (TC Electronic, M-audio, Presonus, Apogee, etc...). They provide excellent DAC performance through USB or Firewire, often for a fraction of the price of hifi-oriented boxes. And if you ever want to get into music making, you'd have the gear ready to use ;-))
I was considering building a system from scratch using a fancy HTPC Case and use a PCI sound card with 24bit/96kHz capabilities, however, I think a second-hand Mac Mini + DAC is a more robust system.
BTW, I find £500+ for a Sonos system is far too expensive for what it does... but some magazines seem to think that it's good value ! Incredible...
