Video editing eats away a ton of disk space. The SATA option will address both your storage and backup issues. I have found that trying to do video editing from a desktop to a server is too slow across a network.
I have had to use Firewire to Firewire network which is built into XP. To move video files from server to PC. I have found that doing all editing on separate hard drives on a local fast PC is best for both rendering and managing video.
I would invest your money into a couple of high end desktops (over a high end server) and a ton of SATA hot swap removable hard drives. That way you can easily store your raw footage, edited footage, rendered DVDs and ISO’s that you may have on really fast high capacity drives.
Two 80Gig hard drive should cover all your music needs to include any mixes that you may be doing. One hard drive can be your master drive and the other drive can be a backup of your cloned music files.