As a tauren warrior, i can only give you one advice that hasn't been featured in this thread already.
Don't pick tauren if you wanna fit through doors.
I mean it.
EDIT: To clarify a bit, undercity doors, a lot of house doors, you'll never fit when you're mounted. specially with a kodo or a raptor. So if you do pick a tauren warrior, which i think is best suited for tanking and possible for pvp considering survivabilty + stun rocks pvp. Pve fury warrior probably orc the best but yeah.
There is a benefit to this, getting a growth potion and running to sen'jin village, making the doctor give you the growth buff and then getting a shaman to pop bloodlust while mounted in ogrimar, makes you a HUGE MOTHER****ER lol.
Edited, Jun 10th 2008 1:50am by ScorpionBlue