... I understand it is a question of file size and audio quality - but is there some good reference information on making a choice? One friend recomends only 128 while another says 356 is a must. Then again, VBR sounds like the way to go, but should I opt for Normal or High. Thanks...
It depends on your needs. If you like to get the best possible mp3 quality then use the High setting as King said. It delivers about the same quality as CBR 320 kbps but saves space whenever it is possible without sacrificing quality. Usually people can't hear any difference between VBR High and CBR 320 kbps. You will not regret if you select VBR High.
If the files have to be smaller you could use VBR Normal. It saves more space and it is still much better than CBR 128 kbps.
Then best thing you can do is to encode some of your favorites with both settings and test them first. Check the file sizes and listen to them critically.
By the way, 320 kbps is the maximum standard MP3 bitrate.