Overall, you are not going to find huge differences between Shades of Green and the other resorts, except that SoG does NOT include Disney's Magical Express if you are flying into Orlando International Airport.
As to the specific question -- AoA's rooms are (much) smaller - Shades of Green is considered a deluxe resort and its rooms are the biggest of all the standard resorts. AoA is a value resort with the smallest rooms.
Bus transportation to the disney parks is via free busses just like all the other resorts.
One benefit is a dedicated bus shuttle service to Universal if you plan to go there at all -- and cheap (10 bucks a person for adults, 5 for kids).
You will also find that Shades of Green is quieter, less crowded, and you will feel less "rushed around". The bus stop is more orderly and less chaotic than AoA.
They have their own website, by the way -- you can check it all out and especially read through their FAQ's which will answer a lot of your questions.