Maybe I should be clearer about what I'm doing and what's happening:
In Disk Utility, to make an image you go to Images/New, and then there are three choices: Blank Image, Image From Folder and Image From (Select A Device).
I don't know why I'd want a blank image. Tried it, and it seems to be just that - a blank image. Image From Folder opens a list of all the folders on the computer, so that's not what I want. and Image From (Select A Device) is greyed out, even when I've selected the CD.
In Toast 5.2.3, when I go to Utilities/Mount Disk Image/Audio CD, it opens a list of the tracks on the CD and asks me to choose one. I don't want to make an image of one track! With the full list, the Choose button is greyed out; it won't let me select all.