Make sure to put those drives in RAID-1 not RAID-0 for reliability.
You'll lose half the space, but mirroring the drives will allow one drive to fail and keep running.
If you have the funds, buy another drive and go RAID-5.
I noticed you selected a PATA drive for the system, I would recommend ditching this drive and adding another SATA drive and go RAID-5 for the entire machine.
Also, a good idea, would be 5.25" hotswap SATA removable drive trays so you can replace a drive easily.
Also, check out the Promise website (http://www.promise.com
) for a list of available RAID cards and enclosures.