n00b question - CD's and MP3 bitrate

[Fistism]

What bitrate should I rip my CD's at so as not to lose any quality when going to MP3? If variable, can someone suggest an excellent VBR ripper / encoder that takes the guesswork out of my hands (and doesn't encode with that high pitched, sounds-like-some-kind-of-cymbal sound that so many MP3's have but that I seem to be one of very few people who can hear)?

I'm asking this because I've been curious about the equivalent bitrate on CD's. I like the fact that MP3's save so much space over WAV (CD), but...

I have a coworker who religiously rips at 320kbps. Is he, as I think he is, wasting room, essentially -- analogously speaking -- blowing a 300x300 resolution bitmap up to a 450x450? Is he wasting space?

I don't want to lose any quality, but I don't want to lose space either. Yes, I can hear, even with my crappy at-work sound system, a clear difference between 96 and 128... Is there any reason to go above 128?

Thanks in advance for your input. Video encoding is so much easier...

-tl
-www.snapstream.com