Slip up,
As BA crew that operated on the 777, I would agree with the majority and say 4 across in the centre seems to be the most popular. That way, you have the children on the two inside seats next to each other, therefore able to play card games etc. while you and your wife are able to sit either side of them. Due to the fact you will be facing the other way, you will be able to keep an eye on them easily throughout the whole flight. It also seems to make the parents more relaxed as no one can disturb the children and the children would struggle to get out without disturbing you or your wife, leaving you able to relax and enjoy a glass of bubbly too!
I also have to echo others in that we very rarely have problems with the children in club. It tends to be the adults!
I hope you all have a safe and enjoyable flight,
Jsl