I've flown with both my son and daughter. My son, who is now 4.5 years old has always flown in a seat and in his carseat until he was 3 (he outgrew it and was big enough for the seatbelt). He always did great. My daughter has flown twice as a lap child. The first time was not by choice. We were taking her for medical treatment in Chicago and the tickets were donated to us. She was 4 months old and did great. The second time she was 13 months old and it was AWFUL! She did not want to sit still and she cried at times. We are flying at the end of the week with her in a seat in her carseat. Hoping it will be better. FAA rules state that children cannot be seated in the emergency exit row (can't remember age cutoff) and you can't use a carseat in the row immediately in front of or behind the emergency exit row (I found that out yesterday and had to change our seats via customer service on one of our flights). I would try not to be over the wings as they tend to get the noise from the engines. If possible you may want to be toward the front, but honestly it won't matter that much because I've noticed it generally takes longer to get off the plane when you have a carseat to move so you might as well wait. The exception may be if you have a very short layover. By the way, make sure your carseat has a sticker on it that says it is FAA approved or they will not let you use it (we've had ours carseats checked by airlines before boarding).