Assuming you are flying in F cabin on the A380, the noise level on the forward of upper deck where all F cabins are situated will be the quietest and the least bumpy part of the plane during turbulence. However, 4A 4K (last row) will be slightly noisier due to the first galley behind, but you can always ask the crew to be a bit gentle with opening/closing the containers if the noise bothers you.

on the 777, F cabin is again the quietest part of the plane, but this time the galley is in the forward section of F cabin and the lavatories are shared between F class passengers/pilots/crew, whereas the A380 lav shower spa are solely for the passengers.