I think that Emergency Medicine prepares you well for Step 2. Although there aren't too many code or ATLS questions, the basic approach to a patient is emphasized (IMHO)... and a lot of people overlook the dangerous things that may present that way... thankfully EM trains you to think "worst first"... which helps on the boards, I think. I scored a 99%ile but do not accredit much of that to my actual intellect but more to my 3 months of EM electives.
Q, DO