My two pence.....
If you are asking the question then my answer is do not do it.
ST is correct, a RAID 0 will speed up load times of your os and some applications. It is great when you need to access very large uncompressed data files. Working with NLE video editing and animation for instance (what I use it for), it can add quite a bit of performance.
The down sides I have personally experienced:
You break the stripe, you lose the data.
Running 2 os's off the same hard drives can cause problems for back up programs.
Over clocking can cause the stripe to fail.
A power outage during a read/write operation can cause the stripe to fail.
A software bug can cause the stripe to fail.
A buggy BIOS can cause the stripe to fail.
My observations of the various reviews of RAIDS... They are significantly faster at benchmarks but not for many applications. Those that take a long time to load, such as large games, are usually slow due to the need to uncompress the files. A few due benefit though.
I am constantly looking to squeeze that last bit of performance out of my system, but I balance that with the risk of having a failure. After several years of trial and error, my main system is 4 os', XP Pro, XP 64, Vista Ultimate 32 and 64. The XP's are on their own partitions on their own 300 gig WD SATAII, same as Vista. I have 2 WD 500's in a RAID 0 for data only. 1 WD 300 for swap files/cache files. I do daily backups of the RAID to a external 1394 drive.
Those drives you have are fast and will perform real well. The first time your RAID fails, the time you spend reloading and rebuilding will more then offset any savings you gain.