Of course there is substantial overlap between areas, but here is a rough guide. Epistemology is the inquiry into the nature of knowledge. Metaphysics is concerned with the fundamental nature of our world. Ethics is the investigation into the nature of moral judgement and moral reasoning. We want to know what actions are right actions.
Logic is broadly the analysis of the structure of correct reasoning.
At issue here are rules of inference and properties of various logical systems. Logic is of intrinsic interest to philosophers as well as serving as a necessary tool in philosophical, mathematical, and scientific inquiry of all kinds. The Philosophy of Science, for instance, is concerned with the nature of the scientific method and the structure of scientific explanations. The Philosophy of Language is concerned with issues like meaning, truth and reference as well as with the explanation of human linguistic understanding. The Philosophy of Mind asks, among other things, whether the mind is the brain and whether reasons can be causes.