Tom, new drives fail on me all the time, I don't trust them until I've burned them in. I've probably warrantied a dozen drives in my life, some just click-dead when you plug them in, but some seem okay for a while until they get hot. I decided it was best to expect them to fail and have redundancy, sometimes multiple redundancy.
BDA,
Simplest is a Win7 mirror. Install two identical drives, then use Disk Manager to set them up.
Next step up is a mobo mirror (RAID 1), if your board supports it. These perform better, but I worry about the data if the mobo dies.
Next up again is a dedicated add-in card that provides RAID capability. I have one that communicates to a pair of little SanDigital 'toasters' with 4 drive bays each. I run those as RAID 10: two drives are paired up to (almost) double read/write speed, then that data is cloned to the other 2 paired-up the same way. I have lost drives from this array several times, and power supplies in the toaster boxes themselves, data survived.
Finally, I like the Western Digital 2-drive NAS boxes set up as mirrored. Slower, but you can put them in another room for disaster security on critical data; irreplaceable family photos and such. Newegg just had a 4T on sale for $280, and I see it's just arrived at my house...that'll bring me up to 36T spread over 8 IP addresses, not counting boot-drives. All of that is mirrored or RAID5, so I have something like half that in actual capacity.