Put 2 drives as master- slave on IDE0.
Put your burner/DVD/etc on MB IDE1 (rumors of compatibility issues on CPI cards).
Then put two more HD as master slave on the first MB Raid IDE channel (IDE2?).
Ditch the PCI card unless you have more than 8 HD/Optical drives total.
You can play with striping but after looking at performance numbers, data integrity risk, etc. I don't do any Raid.
Striping increases risk of data loss and has arguable speed improvements.
Mirroring guarantees that you get a virus on your proimary and mirror at exactly the same time. I make a weekly image backup to a normally disconnected HD after defrag and antivirus check. (Well ok, sometimes it turns into monthly.)