I went alone, without my husband to Europe last year with my 2 kids 18m and 4-1/2 at the time. We flew to Europe and then had 3 short plane rides within europe.
It wasn't as bad as I thought.
Do not bring any car seats. My older one had his own seat and the 18 m old didn't. They put me in the middle row where there are 3 seats, I was right in front in the very first row.. as soon as I got on the plane, they asked the person sitting next to me to move, so I would be a little more comfortable (the person was happy to move away from the kids anyway). This way I had all 3 seats available to myself.
As far as seat belts and safety - They give you a seat belt that attaches to your own seat belt for the baby to use during take off and during landing. They also gave me a large pillow/mattress thing, so I could put her to sleep on the floor in front of my seat.
Bring variety of snacks, pacifier, suckers, offer water or milk or juice during the entire take off and landing, that helps with the ears/pressure.
Bring a stroller and gate check it for the baby. YOu can use it all around the airport and collapse it by the plane entrance, they will have it ready for you when you come out after landing.
Try to bring the neccessary items only. All I had with me is a backpack - with kids stuff- diapers, wipes, change of clothers, snacks and a few toys, coloring books. I also had a fanny pack around my waste with the travel documents. Thats all I had and I'm glad I didn't have any more junk to carry around...
They slept most of the way there as we left at 10pm, and were really good on the way back also even though it was a day flight...., I was surprised.... Good luck and have fun!