Need help Deciding on Raid Set up.

Edit: Going to simplify the Question.

I am looking for either redundancy against Physical Failure or Back up against Physical Failure, I'm not worried about viruses or anything.

Performance is just a boost, I'm not a super heavy gamer anymore so I can handle an extra couple seconds load, more of my Pickyness comes down to the FPS, and my Eyefinity set up not the Second or two of Load time. BUT I do worry about losing all of my Data.

So I don't want to go with Raid 1 since its absolutely useless for my application.

I currently have 1 WD 1TB WD1001FALS, Unfortunately one of the more expensive discs compared to other 500 or 640 models, so setting up a Raid 5 or Raid 10 with this disc would require a bit more $$$.

Reason I would not want to use a Raid 0 would be No redundancy between the two discs even if I were to say use two new 500gb in Raid 0 and this disc as a 100% Back up, so at that point I would feel more comfortable just adding 1 more disc and just accepting the 360 or 500GB Slack since 1TB is more then enough for me for life.

I do not plan on blowing 200$+ on a PCI Controller and would be using my Mainboards controller. (Maximus Formula 3)
And I would not have the xtra $ to blow on a UPS.

So bit difficult at this point looking at my Options.

Essentially I am looking to get what Performance I can without risking Data, I want to do a Raid Array because I wouldn't feel as if a Back up disc is going to waste just mirroring my Main disc, Given that though I doing a Raid Array with my hardware circumstances I don't want to risk killing drives needlessly in say Raid 5 or Raid 10, Due to AC failure or Mobo Crash... etc?