PSM

I recently had an issue with my current 500GB hard drive and almost lost some files, so I've decided to play it safe and just purchase two new 2TB internal hard drives for my desktop to keep each other backed up. The 500GB will remain installed as a third drive in case I forgot to back up any files from it but it won't really be used for much except access to old files I might have missed, or maybe a third-level of backup for really important files (you can never be too safe with backups, I've come to realize).

One of the 2TB drives will be the primary drive and the other just a backup of the main one but I was thinking: is there any reason I can't or shouldn't install Windows and all of my software on both hard drives so that I literally have another one to just boot the system from and run everything off of if I ever have an issue with the main one? Is there any downside to this aside from taking up some extra space on the second hard drive for the OS and software?

Also, if I do this, are there any options for actually mirroring the two drives somehow so that new files are backed up onto the other one automatically, or will I always have to click and drag to back them up? I know some sort of RAID setup would probably work, but I know very little about RAID (just started doing some research on it) and I don't know if it would affect my "installing Windows and software on both drives" idea.

Thoughts?

PS - If anyone has any advice on which drives I should go with, I'm always open to suggestions. I'm researching those right now, as well.

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Built 01/08/08 - XP Pro, Ultra Aluminus Mid Tower ATX Case, XFX nForce 680i LT SLI Socket 775 Mobo, Intel Quad Core Kentsfield 2.4Ghz Q6600, OCZ 2048MB PC6400 DDR2 800MHz (2x1024MB), NVIDIA GeForce 8800 GT 512MB PCIe, Seagate 500GB Serial ATA HD 7200/16MB/SATA-3G, Ultra 600w X-Finity Power Supply w/2 80mm / Titan, THERMALTAKE RSI Socket 775 CPU Cooler, 2 Cooler Master 120MM Fans, LG L1953TX-BF 19" 5ms DVI LCD Monitor