so wait....you want to set the 2 80GB on raid...and then set another RAID up to back up the RAID array you just created?
I believe that your going to want RAID 0 with the 2 80gb for nice performance and then RAID 1 backing up the Array you have just created. I don't know too much about RAID though and this is just a guess.
Yes RAID work with IDE...it was created years ago before SATA