My favorite single-aisle is the A319/A320 - the extra inch of seat width in Economy makes all the difference. The LCD IFE is a bonus.
For dual-aisle, 777 and 767 all the way (again, that extra inch in Economy).
My only experience on Airbus dual-aisles were two Air France A300s in 1985. The first was the shuttle between Heathrow and DeGaulle, so that was cramped to all heck. I did fly First from Athens to DeGaulle and that was amazing.
Still, from what I have seen, I'd take the 777 over the A340.