I'm planning to host a luncheon (or brunch) on a Sunday in December for my mother who is turning 95 and sharper than I am. Can any of you recommend a restaurant in Manhattan with a private room that can accommodate approximately 45 people? I'd like to keep it under $80 a person, tax and tip included. Any neighborhood is fine--the only limitation is that there can't be a large flight of stairs. Thanks for your help.