For hard boiled eggs, the quicker you can cool them from boiling to fridge temp, the better they will peel. If I get them into ice water (with plenty of ice cubes) right away, and keep them in the ice water until all the ice has melted (typically about 45 minutes), they peel very easily, even more than a week later.
Slow cooling (as in just water cooling them) will have most of the white sticking to the shell.