Thats a great collection. The only thing that is a miss in the tank is the frogspawn. They need a 6" radius from other corals because they have stinging tentacles that can hurt/kill other corals. I had one in my 10G and had to move him to my 150G to get him far enough away from other corals. He was fine when he was small but then he began killing the xenia stalks which is no major loss as it grows like a WEED.
The little round polyp things are really neat, they are called zoa's, paly's, polyp's, button poly's ect. They stay small and dont spread fast and are easy to care for. The Acan or brain corals are about the same a growth too and are pretty easy to maintain as well.
The green stuff on the back glass is green star polyp and the white stuff next to it is Xenia, these both grow like weeds so you will be trimming it back and giving it away or throwing it away so dont feel bad if you get this coral and need to do so.
Also for coral ID and a good learning site go to liveaquaria, they have a great site with good info and great pics of what they are talking about. The corals are even broke down to beginner stuff and Nano. I would look to the Nano stuff as this will be stuff that stays small or grows very slow.