I have a degree in computer science, looking to learn more about math to apply to a math graduate program and for fun.
My guess is that if you have an interest in computer science, you will have the most fun with logic and discrete math, and will not have much fun with the calculus.
If you are serious about getting into a math graduate program, then you have to learn the calculus stuff anyway, because it is a large part of the Math GRE.
If it's worth saying, but not worth its own post (even in Discussion), then it goes here.