Why a minor at all? Minors are the most over-rated part of college academics to start with, and to do one to prepare for a standardized test is inexplicable logic.
Pre-med recs & reqs are typically a year each of general chem, o chem, physics & bio, plus a semester each of psych, soc, and biochem. With those courses taken, prepping for the MCAT is basically test prep.
Use your electives to take classes that are genuinely interesting to you, whether they relate to your major, your intended career, or just being an interesting person.