start vc at 15-20, sfk at 15 also. stocks at 22 i would guess. then SM.

bear tanks are great. every single healer i've spoken to told me they love healing my druid over my unholy tank dk, over my prot pally, and over my prot warrior.

tho druids have less bells and whistles than dk's, they're not as reactive as pally or warrior. do note that they're all different tanking styles and tank differently from one another. you might want to experiment also. tho i've found warrior tanking the most challenging of the four, especially with multiboxing.