Hard disks are prone to breaking, I'd suggest getting a NAS box that can run a media server with at least 2 disks that can be mirrored (RAID 1, the disks automatically contain the same data) so that if 1 HDD breaks, as long as you replace it before the other breaks you'll not lose your data... re-ripping all your CDs,downloading again from Amazon etc etc is a PITA depending how many albums you own. The D-Link DNS-323 is pretty good for this.
Then you can stream the music anywhere on your network from the same source using the client of your choice, e.g: WMPlayer on your desktop in the study, your TV/Stereo via a PS3/XBox/Squeezebox in the lounge, a standalone hi-fi type client in the kitchen.