I wouldn't base my decision on using it in a crib. It isn't safe to have blankets in cribs with small children because of smothering. A friend's little girl who was 10 months old at the time smothered with a blanket in a crib when a baby sitter was watching her. Very tragic. The child is more likely to use the quilt on the floor to lay/play on, drag it around and snuggle with it. Either shape is fine but I would probably go with square to keep the pattern in tact. Really like the pinwheels.