Help! My RAID disks screwed up

My S2003 was set up using RAID-1. After power outage, the boot process showed error on D drive during reboot but the system was still. I though I could use CHKDSK to fix so I did. It ran through C and D and some files in D were fixed. The first boot after CHKDSK complete showed an error something like ISSAS.exe error. Then I rebooted it and getting “Reboot and Select proper Boot device or Insert Boot Media in selected Boot device and press a key”. In order to boot up the system, I need to use the installation CD to do so and pretend to do automatic recovery (F2) and cancel it (since I don’t have a diskkette). Addtional info about the disks, at the very first screen during system boot, it shows RAID-1 degraded, one HD is normal and one is missing.
Is there a chance I can RAID-1 can be reinstate? If yes, how do I fix it? If no, then what’s my alternative?
Someone has mentioned that Microsoft would allow S2003 to be reinstalled even it was activated but I dare not to take a risk to reinstall the whole thing. Your help/advice is greatly appreciated.