The most noticeable difference is the change in bodywork. There were internal engine improvements and changes in in engine placement for 2002, but I honestly doubt that any of us street riders will notice or benefit from those changes. That is an amazing price for an R model, it is $500 less than I paid for my standard model 2000 a year ago. Considering the difference in price between the 2000 and 2002, you could use the money you save to modify the 2000 to be much better than the 2002 with its improvements. Sit on them both and see which feels better to you as there is a difference due to bodywork (particularly the tank).
I could have been a squid, but I was too busy posing.