Ok, but what's the point of trying it to see what happens when you now know that installing XP on three different drives isn't actually going to make any difference when it comes to being able to recover from a crash. It also means that, to keep a contiguous experience when booting from another drive, you're going to have to maintain data and file parity between all three drives. Otherwise, if you decide to boot from, say, the second drive, you won't necessarily have access to the same files and programs that you have on your first and third.
It's a big headache with little to no benefit for doing it. Personally, I think you're better off following Hymie's advice and investigating the cause of your computer crashes. There has to be some sort of underlying problem for them to be occurring, because XP is an otherwise very stable operating system. If you found out and fixed what it is that ails you, then you could forgo all that effort and have 2 additional drives for storage and backup.