A.--Good luck! My suggestion is to take you car seat on the plane. I've flown with my daughter numerous times, and it was much easier to do when I had her car seat with me on the plane. It kept her "contained" In just the regular seat, she was "squirmy."
I usually check my stroller at the gate. On my last flight, I had my almost three year old walk (pulling her very own Dora backpack with wheels which was full of books, crayons, snacks and DVDs), I put my son (6 months)in a sling, and I piled all the stuff on the stroller. A six month old in a sling is easier to carry than a big car seat!!!!
I also sat in the front row of the plane (we flew Southwest and they have open seating). This was nice because I had a little more room and I didn't have to worry about my daughter kicking the seat in front of her. When she was younger, we used to sit in the back of the plane. It's bumpier back there. I liked it back there because the bumps would lull her to sleep. I guess it depends on the child.
On our last flight, I brought her a lollipop. I also practiced "screaming quietly" with her. I'd count to three and we'd open our mouths really wide and pretend to scream. I figured these would help her with pressure in her ears. I guess it worked..because she didn't cry about it! Ha ha!
Good luck! Traci
P.S. ...make sure she's not screaming in the aisles! You don't want to be kicked off the plane! That poor family! Although, I bet if they'd had a car seat for their child, they wouldn't have been thrown off!