Right, the digital dl is 320kbs mp3 and a lossless (FLAC or WAV) rip is 16/44, which is better. How much of a difference you can hear between the 2 (lossless or 320kbs mp3) is very debatable. I'd say the better your hearing the more likely you can tell a difference.
Mp3s are compressed into much smaller files and WAV files are bit for bit, from what I understand. I rip all my stuff to FLAC files, which is somehow compressed but still lossless on playback. I kinda get how it works, but don't want to attempt to explain it, lol. FLAC files use a little less space than WAV and are just as good so that's the format I use.