First of all, let me ask what your reason is for going to grad school. Are you interested in the degree for an MPH, or do you need a little more work to prove your "worthiness" to be accpeted to medical school?
I my opinion, a lot of people take the MPH road just because they've heard that that is the way to go if you intend to apply to medical school; I almost did it. If you really want or need grad school I think it would be in your best interests to take classes that you are interested in (not because it is popular). You'll have an easier time studying something you like as opposed to something you are disinterested in. Plus, it will be genuine when you explain that to the acceptance committee during interviews.
In my case, I didn't do so hot in undergrad and decided to go to grad school for my Master's in Biomedical Sciences. The classes are mirror images of the clinical-based medical school, taught by several of the same professors who teach at the medical school (i.e. Histology, Biochem, Physiology...)
In addition, it was said that ~80% of the people who graduate with the the MBMS degree get interviews.
So, just do your research and figure out what is in your best interests. Don't give up.