Hi David,
[code]
--- rd:3 wd:1 fd:2
disk2 , 0:1, dev:sdc2
raid5: failed to run raid set md2
md: pers->run() returned -22
md :do_mdrun() failed ...
md: md2 stopped.
md: unbind<sdc2>
md: export_rdev(sdc2)
looks like you have (at least) a faulty partition : sdc2
The system was not able to rebuilt the raid , it should have be OK we 2 disks from a RAID5 installation, may be there was some other problems earlier you did not noticed.
As Murphy helps, this partition (disk) was part of the main "data" array (/dev/main/root) and if you really loose two disks (partitions) from the raid, things are done

if you loose only one, you might try to boot from a live CD (with raid and LVM support) and look further accessing a degrated array (I won't be of any help for this)
G.