Storage of image files

I have read that images stored on todays DVD's or CD's will start to go bad in about 5 years. This is a real concern since I make copy of originals on CD or DVD.

Right now I am very careful and probably too careful. I store RAW, JPEG and some times PSD on external drive and back that up on CD or DVD and another external drive.

My situation is now that I am getting more and more images out there to save, I fell the back up on 2nd hard drive is going to be hard to continue. I now am fillilng up 2nd hard drive (smaller ones 150 GB and 200 GB), and I then back them up to a 500 GB drive.

What are others doing. Does the 2nd hard drive back up make sense. Right now I don't have edited copies backed up on CD or DVD just the RAW. Should I back them up on CD or DVD as well. But if the 5 year issue is real, what value is it?

What are others doing

Multiple hard drives. Currently between 250 GB and 1 TB drives.

Just thought of something else. Since I am using LR and the cat are on my computer hard drive (assume that is where they are the program is there)? Or is the library info stored on the same drive as where I am storing the images (external drives)???

If all this is on the computer (internal hard drive) I guess I have a way to go back to original if needed??