I'd recommend the Marriott Suites mid-town. Rooms have a separate bed-room with French doors into a living room with sleeper-sofa. The hotel is on 14th St. near Peachtree. The MARTA station is 3 blocks north. Colony Square is 2 blocks away. The High Museum is close by. There's a lot of good restaurants within walking distance. Atlantic Station (lots of shopping, restaurants) is a short cab ride away.
When I took my wife there for her birthday, I seem to recall we were given free breakfast but not sure about that.