There is a nice File, Edit... menu that goes along with it.
Close your eyes and pretend the rest of the complexity doesn't exist and it will be no different than using Notepad, etc. When you want more, open your eyes a little.
I would strongly recommend against using aquamacs as it uses non-standard config locations which can be a giant headache. It writes saved configs into the ~/Library folder verses .emacs and it's very easy to create conflicting configs where .emacs is overridden. They may have fixed this, but that's how it behaved the last time I used it. This also seems to be the general consensus in #emacs on freenode. I'd recommend using Carbon Emacs on OS X instead. http://homepage.mac.com/zenitani/emacs-e.html