Thanks Anthony and Eldio - you gave me this advice on AIFF on another thread, but I thought WAV was also lossless - wait, you said that! Any way, I tried exactly what you suggested on my own and guess what - the tracks that are freezing up in iTunes are also freezing up via this method. They can't be read. I actually think I have scratched up CDs and just had the luck of trying a few scratched disks in a row. I'm going to try another external CD drive I have around here and/or my handy CD resurfacing kit too. So, thanks to both of you, I think I have this rather silly situation figured out (Anthony's mentioning scratches got me thinking). Still, it would be nice if iTunes could have told me it was having trouble reading the file! Just freezing is not the best way to communicate with the old user!
P.S. I can PLAY these troublesome tracks from the CD and not hear any obvious clicks or skips, but I think playing and reading into memory are two different animals in terms of how the computer can handle errors - no?