A falcon (Peregrine maybe?) or hawk? FLIGHT THANK YOU VERY MUCH YES. Plus, unlike some of the other usual suspects (Lion/Tiger, Wolf, etc.) I'd more likely get people who might want to shoot me with a camera, rather than a gun XD And unlike with say, 'dolphin/whale', I would be able to make use of the form almost anywhere because 'Outside' usually isn't far away, and I presume they'd have at least a small degree of cold weather protection.
Kill it with fire! What is the 'it' that you first think of?