What hardware and what OS level are you at?
You can choose to do an archive and install to reload the OS without loosing the applications.
This will not change the current drive statistics which should be HFS+ Journaled.
Don't choose the UFS (Unix) file system for this.
Like I said, which hardware and what OS level?
I assume that this is a MacPro because three 500 GB drives are RAID'd as RAID 0.
If this is a RAID hosted by the OS through Disk Utilities, you will loose that RAID set when you reinstall the operating system. The system provides a software RAID 0 which is very fragile.
You will most likely loose every file that is on the current RAID 0 volume once the OS is reinstalled.