Only if you did poorly in them. If you're worried about not remembering much going into organic chemistry, then don't be. The first two chapters in organic are a review and cover all the gen chem you need to know.
Adcoms want to see some recent academic aptitude in the sciences, so instead of wasting time spent on repeating courses, take some upper-level sciences, like biochemistry or genetics.
Also, you might want to take an MCAT prep course to refresh your memory on some basic concepts of gen chem and physics before you take the test.