I would disable the raid and run diagnostics from a bootable utility cd on each drive to find the possible faulty one. The drive that gave you the critical error may have been caused by an incomplete array. Run tests to find any bad clusters. Then try booting to that drive again while the is raid disabled. There should be backup copies of the registry so you should in good shape. If you can boot normally with one good drive, then you should be able to rebuild the array. If the other drive proves to be bad just replace it and rebuilt the array. If you feel the other drive is still good then zero it out and then rebuild the array.
This should come in handy.
Ultimate Boot CD - Overview