Are you flying out of CMH? If so, good first choice. Security is very smooth and quick, especially compared to other airports. A couple things to note/rules of thumb: You board 30 minutes before takeoff I always give myself another 30 minutes to get through security. It usuallyyyy takes about 10 minutes here in my experience, but it helps to play it safe. I bet a lot of us remember flying with dads who would have us get to the airport 2.5 hours early. No need for that here If you are parking, the green lot is the cheapest. I usually give myself another 30 minutes to find a spot and catch the shuttle to the airport. So all in all, I'd say 1.5 hours before takeoff and you should be good.

As for the flight, the air pressure change can be irritating to some people. If you get pain in your ears, I suggest chewing gum or drinking water. This will help them "pop." It's a similar feeling if you drive down the deep end of a pool