I not sure why you would want to try that kind of setup, to be honest your better off just leaving them all as single drives.
The ssd is way fast enough to install the os on for quicker boot times and running your most important program or to quickly launch fave program from the ssd.
You don't get much of a speed increase anyway, by doing a raid of two 500 Gb HD.
You will go from 90 in crystal mark to about 160 if your lucky, on read and write performance.If your not bothered about redundancy of data why bother. If you were talking about a few Solid sates then i would say ok.