ok, I've been on the 777 twice, once in coach, once in bizfirst. Coach was not bad. As you already know every seat has its own PTV on the seat back of the chair in front of it. Got your choice of movies and games. People have said that its a little roomier than most other planes but to me it was no difference.
Now, Bizfirst..that was awesome!!!!!! The seat is like a lazy boy that you have in your house. I loved it. You will definitely be comfortable that's for sure.
Both the times I flew on the 777 was EWR-IAH so i can't say how the INTL service is, sorry. When I get my A & P licences and transfer over to MX, maybe 777gk will let me jumpseat on his flights!