just got sapphire yesterday and i started out with mudkip. I'd pick torchic though if i were you, because there are plenty of grass and water pokemon you can catch early on, but i have seen no fire types yet. a good early team would probably be torchic, ralts, wingull, shroomish or lotad, taillow, and makuhita(trade a skaloth to a girl in Rustboro city to get Makuhita). poochenya has also been useful for me, so has skaloth since he is the only pokemon i have taught cut to.