Can anyone suggest a good (and free) converter to convert the files in to *.WAV files such that can then be burned on to an audio CD?
Windows Media Player 12 should be able to handle *.m4a=AAC= mp4 audio only files, so if you have a laptop with Win 7 you could use that. Easier to queue from that or an mp3 player that will play them than from a CD in a player.
If you are not an applephobe, Itunes is the application that was designed around this format. I believe it will let you do the conversion to wave, and maybe even burn an audio CD directly. It is a free download for windows, but don't listen to me. I am an applephobe. Also there may be DRM issues.
And I assume you know that copying *.wav files to a CD will not make a CD that will play in a CD player.