research isn't necessary to get into medical school, although the "top" schools are at the top because they have heavy research focus, which means that they want to bring in students who might also be interested in research.
that being said, do you have any reason to not do research? What I mean is, when you think of the possibility of doing research, do you really dread it, or do you just not have any interest in it? If you dread doing it, by all means, don't do it, but if you don't have any interest in it, I would recommend giving it a try. If you don't like it, you don't have to keep doing it (and if you are asked in an interview why you stopped, you just say that it wasn't for you). If you like it, that's awesome, and it will definitely make you a better scientist.
I find research to be so much fun, and, in reality, undergraduate research is the best, because there is almost no pressure on an undergrad. If you want to do research, join a smaller lab, because the PI in a smaller lab will be more likely to be directly involved in training you, which is really good.