My boys (now 6 and 3) have done many, many transatlantic flights because we lived in France for the last 2 years for my husband's job. The flight over is the easiest, because you usually travel overnight. By the time you do dinner, you can put on PJs (or just travel in comfy clothes) and sleep the whole way! On the way back, the boys would usually watch movies (we liked to fly Northwest or Air France for the tv's in every coach seat), color, and play games. We did a Med cruise with them when they were 5 and 2, and they loved it! We did NCL because Disney wasn't over there yet, and they still LOVED the kids club, which was no where near as big as Disney's.