This is my workflow: I take raw, modify, convert the ones I like to jpeg. However I found the jpegs were still 8mbs; too big for my hard drive.
My solution: jpeg 2000. I'm now going to convert my jpegs down to under 2mb fro my hard drive and burn the raw files to dvd.
What compression rate would be most appropriate? I conducted a test of 3 different types with a small strip from a photo I took of some bark. My impression is the 80 percent quality is virtually undetectable from 100, but that at 50 you can see artifacts.
80 seems like the best way to go.

