I just found out that AA (not sure about SWA) doesn't allow carseats in the row in front of and the row behind the exit row. However, it does not sound like it is heavily enforced. I would try to avoid these seats if others are around.
I'm flying with a carseat for the first time tomorrow, so I won't have any actual tips until next week! However, I have seen posts where one parent boards with the carseat and installs it while the other parent plays with the children until towards the end of the boarding process. This delays the amount of time the kids have to sit on the plane and helps them burn off some steam. Of course, this only works with two adults.
My daughter is a pretty well behaved 3 year old and she is really looking forward to her "first" flight (not really her first, but she doesn't remember the others). On the other hand, I am starting to worry and packing a lot of toys from the dollar store and little snacks. We frequently go to
Disneyland and she is very patient about waiting in line. But in this case she does have a few inches to walk around and we can shift between holding her and letting her stand and circle us in line. Moreover, if she has a complete meltdown -- happens with the ALL kids at times, they get hot, tired, etc -- we can always exit the line and either leave the park or distract her away from the crowds of people. Unfortunately, on a plane, she will be stuck in one seat for the entire 5+ hours. I'll be keeping my fingers crossed.
If your little ones are really impatient by the time it comes to get off the plane and there are 2 adults, you could also have one adult deplane with the kids and the other stay and remove the carseat. This way, you won't hold up the plane, but your kids don't have to try to be patient after a long (and probably boring) flight. It is really hard for children to watch everyone else leave while they have to stay seated. Of course it is our job as parents to teach them patience, but it may be easier to avoid the public meltdown and teach them this in other, less crowded places! Especially if you are traveling with a carseat. I am assuming that one child is probably age 4 or under -- they are just learning reasoning and have no concept of "a couple more minutes".
Have a wonderful vacation and an uneventful flight,
Jennifer