I thought that commercial CD's are different from CD-R's - the 1's and 0's are physical dots instead of little burn marks. So I don't know if that theoretical 100 year shelf life applies to CD-R's.

Also, poor grade DVD's (I haven't heard this about CD's) degrade quickly. One of my friends said that he left his DVD out and then picked it up and saw physical holes in it as the ink shifted. So you definately want to buy high quality CD's for archival purposes.

I propose you get a microscope and examine the surface of the CD-RW and then chisel the dots you see onto a giant stone wheel. That ought to last a lifetime, as long as you don't drop it or leave it out in the elements. Maybe store it in a cave somewhere and future civilizations can discover it and it will be the rosetta stone or dead sea scrolls of their day.

Seriously though, I don't know that any digital storage element will last into your old age... This is a common discussion in the audio forums I hang out in. They feel that analog tape will last longer than digital simply because a tape machine can be built easily from parts, whereas a computer will be nearly impossible to build. The great thing about real photographs is that they don't require a reader. You may find yourself transferring your collection, and an image viewer and printer, to the next big archival storage format in 10 to 20 years, or keeping a computer around and hoping it continues to work.