There are really two strains of Labrador - the conformation or show type, and the field trial type. If you want something docile, go with the conformation type, they are much calmer couch potato type dogs. They are also shorter in stature than the field trial dogs, and heavier in build. They are usually perfectly content to just "hang out" - at least once they get past the puppy stage (and Labs tend to be puppy-like at LEAST until age 2).
The field trial dogs are bred to demonstrate flair and drive under the difficult and grueling conditions of a field trial or hunt test, and to hunt all day in swamp or cornfields and still be brisk enough to run down a wounded bird. They are brim full of go and energy, and your average home doesn't give them near enough work to do. We took up agility and hunt tests in self defense, just so Shelley would be plumb worn out by the end of the day.
Chocolates tend to be of the field trial type, because the gene pool of chocolates is relatively small. So if you want a quiet dog, I would go with a black or yellow conformation type Lab.
Shelley is a hybrid - her sire is a conformation champion, her dam is the daughter of the only Chocolate Lab ever to win a national field trial title. She has some characteristics of the conformation type - she is of very short stature and has a fairly short muzzle as well as the true "otter tail" (which many field trial dogs have lost) - but her slenderness, her birdiness, and her personality are all field trial.
Conformation dog - Shelley's dad.
Field trial dog - Shelley's (famous) maternal grandfather. When you mention at hunt tests that Shelley is a "Rascal granddaughter", people go "ah!"