the quick summary is to pick the skinniest tire and the smallest wheel for the winter package. The skinny tire will dig into the snow and find the packed snow for traction and the sidewall will protect the wheel from damage. As for car prep, start with snow tires, add mud flaps to protect the sides of the car from abrasion, wash and add plenty of wax to protect the paint over the winter months, add winter floor mats to protect the carpet, and check wipers and wiper fluid. Something that I did not mention is to clearcoat as much of the suspension bits as you can to protect them from the salt.