I need a drive (or two) to replace my crashed Seagate 7200.11 drive. I will only use the replacement Seagate for my media server with a good backup.

I was using about 500gb of the 1000gb drive. I am looking for suggestions if i should get two 1 TB drives and use one as a weekly backup drive or if i should put them into a RAID setup. My Gigabyte motherboard has a built in RAID controller.

What is the most reliable backup scenario?

What is the best online backup provider? I am considering Mozy, any thoughts?