I fly from Memphis (US) to Manchester (UK) at least once a year with a connection in Atlanta. It makes for a really long day, but it can be quite fun if treated as an adventure and if the traveler is well prepared.
Like @YARNLADY said, if there is a connecting flight, it’s a matter of booking several hours between the flights in case of delays. This aids in alleviating any panic in getting from gate to gate on time. And like her as well, I book the flight to England to start in the late afternoon and to arrive in the morning. That way, I can catch a couple of hours sleep.
On the long flights, the passengers are constantly getting fed. I enjoy the food…it’s like a little picnic and it kills the time.
The other passengers can make or break the trip. One time, I was seated in front of Mr. Cranky Pants who would kick the back of my chair every time I attempted to recline it. I finally looked around. With a glaring look, he said, “There is no leg room back here.” Most of the time though, people are pleasant, and I’ve met some interesting people.
One time, there was a change in planes and the connecting flight was changed to land in Amsterdam before heading to England. By the time we got there, all flights out were cancelled due to a sudden snow. A few people were able to find a hotel room, but the rest of us claimed a spot on the floor or in a chair to wait it out. It was quite an adventure.