I can’t find any kind of “Life in the White House” cite offhand, but here is what I’ve culled from the various sorts of Parade-type magazine stories I’ve read over the years.
The White House is run like a private residence, with a staff of cooks, housekeepers, maids, etc. The kitchen has an executive chef in charge, with a whole platoon of other chefs under him, and the First Lady (and the Mister, if he’s so inclined) consults with him on menus, exactly the way she (or they) would if they were living in a big fancy house anywhere else. He cooks for them, not for the People of the United States of America, so if the Prez hates broccoli, broccoli doesn’t appear on the menu (at least, until the Broccoli Growers Association hears about it, in which case it abruptly makes an appearance).
Menu choices for elaborate state dinners require more consultation with various etiquette and dietary advisers than do family suppers. And if the Prez hates broccoli, but the Broccoli Growers Association is coming to dinner, then broccoli appears on the menu, and he’s expected to at least taste it (and without making faces, too, thank you very much…)
The White House chefs (plural) are also responsible for tasks like making thousands of hard-boiled Easter eggs for the White House Easter Egg hunt. Lucky them. 
If the Prez wants a PBJ in the middle of the night, he is perfectly at liberty to go down to the kitchen and make it himself–if he cares to brave the wrath of the Executive Chef. Most Executive Chefs are notoriously territorial about their kitchens and would prefer that the Family stay out of them, and let a staff member fix the sandwich. At least he knows the Staff Member will know better than to leave a peanut butter knife laying out on the counter… 
There is a private dining room, as well as a state dining room, which can seat 130 people.
http://www.whitehouse.gov/kids/tour/dining.html
During the first few months of the Clinton White House, it seemed like all we heard about was “what’s cooking at the White House”. Bill Clinton was fairly characterized as a “big hungry boy”, and I particularly remember the news accounts of a February 1993 lunch he hosted for members of the media at which cheeseburgers were served, and afterwards Tom Brokaw (I think) remarked, in awe, “He ate everything but the drapes…” 
And if you’re really, really bored this morning, you can plow your way through the incredibly banal Barbara Walters/Laura Bush Christmas interview from last Christmas and see if she says anything about the food at the White House.
http://abcnews.go.com/sections/2020/DailyNews/2020_bushes_iv4_011203.html
Me, I have to go watch some paint dry… 