As far as I know once your RAID 0 volume crashes, your O/S will obviously be gone and you may or may not have access to your other volume. I also have a 2TB custom computer that I built using Intel's Matrix RAID and I have had it crash many, many times. I try out different combinations every time and none have been as versatile as I would like it to be. It only worked out once that I had created a separate partition on my system that led to my data being safe. Also ideally, this is how it is supposed to be. But there is still a chance that the system may or may not recognize the other partition properly after an O/S re-install. Thus, out of rebuilding my O/S and partitions 10 times or more, I would say that this trick has worked maybe once or twice. So now I just rely on RAID 5.
So I would say that if must keep your O/S separate then carry on with your plan but as i mentioned there are no guarantees.
