My setup is 1 main server PC running windows 8 pro. MC is always running here.
I have other windows 7 pc's on the lan that run MC as library clients
(see this in the wiki)All media files are on a raid 5 NAS box.
On the server copy of MC, I point the library to the UNC path for the nas (\\NAS1\music)
All importing and tagging is done on that machine.
Now for output, I have HDMI cable output from HTPC machine into my stereo receiver.
I have RTA cables from one sound card going to a small stereo receiver in my garage, and another set going to the pool patio area.
Each of these shows up as a 'zone' in MC and different things can be directed to play at those sound outputs.
Of course each windows PC, has standard sound card with speakers.
I have a couple of android tablets running the android app GIZMO.
This app acts as a remote control for MC and can direct media to play at any of the various zones.
I use this to select movies to play on the HTPC and for pause/play control.
It also has capability of playing the media on the tablet itself, but I don't use it in that mode.