128kb is average audio quality, good for people who arent interested in or know nothing about good quality audio, and will just go into a shop and pick up a CD player that "looks nice"

when you buy a CD, the bitrate is 1411 kbps, so obviously 128 is not cd quality. however, 128 still sounds good (usually no background noise etc) and doesnt take up much space (1mb per minute @ 128)

best mp3 ripper is probably audiograbber, but for a free download you should definately get AudioConvert. this program can convert mp3, wav, wma, ogg, and many other popular formats, back into whichever format you want. ones i use most is OGG-MP3 (when i download an album that some fool has saved in ogg format) and also wav-mp3 is good. as is WMA - MP3. wma is a crap format, only good for if the files will stay on your pc and go nowhere else.
audioconvert - a genius of a program