I want to buy my daughter a new Nintendo DS for Christmas as she says her original one - she bought it herself - is "getting a bit ropey" (she has had it for years). She has had a rough year (health problems) and has been so good about it all that I really want to get her whatever is the best one out there but also want not to bankrupt myself. I know nothing about Nintendos so please can someone tell me which one is a good buy - there seems to be several options.