IMHO Aquamacs is a terrible idea. If you want to learn Emacs, either find someone who uses it and steal their configuration, or learn from the Emacs Wiki. Aquamacs makes a lot of dumb interface choices, e.g. mode-specific color themes and one buffer per frame. Plus, it dials home regularly to report your usage statistics. Use the carbon emacs package from apple.com, which does the bundling without breakage or spying.