Hi Judith.
I want to perserve my wav files after burning to CD, because I may need to burn them again and I may want to convert them to MP3 files for use with an MP3 player.
Convert your WAV files to MP3 ( but to keep good quality I would not encode them any smaller than 192kbs ). You can store these on your hard drive or as data on a CD-R. If you ever want to retreive them, simply convert them back to WAV or if you want to burn to CD-R most burning apps will burn an audio disc straight from MP3 anyway. As MP3s are generally 10 times smaller than a WAV file you don't really want to be clogging up your hard drive with masses of 50MB+ files.
Sound Rescue creates .awf files for both the input an output files.
You don't need these files. Cool Edit does something similar and basically all it does is hold information for Sound Rescue about the file you are working on i.e. undo, redo, cut, paste, etc.