I am doing the same from DFW to DXB in June and after some research I have chose seat 47K in the rear where it goes to two seats, picked window which I almost never do but since that flight is in the 14-15 hour range I figure it will be easier to rest my head in a window seat versus aisle. The bulkhead seats with legroom cost more and there appears to be an issue with people congregating so I chose not to go that route. In the past on a 777-200 from LHR - DFW I ignored the warning about middle bulkhead and the bassinet with infants seated there and paid dearly. Had an infant who was teething and cried for nearly the entire 10 hours. I am connecting to an A380 to KUL and did the upper deck forward twin also, it cost me $320 to chose those seats for the four legs and that comes out of pocket because my company won't reimburse that. Did you read the aircraft and seat reviews on SeatGuru?