Every office has its own lunch culture. Only a lucky few cubicle slaves still get a leisurely lunch hour. The more common lunch ritual is of the e-mailing-with-one-hand-while-jamming-a-tuna-salad-sandwich-down-your-throat-with-the-other variety. If you're unsure of the lunch scene at the new job, better to brown bag it than get stuck with a vending machine lunch of peanut butter crackers and Mountain Dew. You may end up having lunch with the boss on your first day, but that's no guarantee -- and you may end your first day at work hungry.
Either way, start your day with a hearty breakfast. You'll need more than your usual coffee and Cap'n Crunch to sustain you through hours of orientation and hand-shaking.