Get a caliber you can find in the store. The .243 or .270 are very popular deer calibers and can be found just about anywhere, and the recoil is very light. As for the rifle, I'd suggest a Remington 700 ADL as a starter, they're easy to work and clean and very accurate. A second suggestion is the Marlin XL7/XS7, again a very accurate starter rifle. Finally I'd recommended a Savage Axis, good reliable budget rifle and a nail driver at that.