I've stayed at all three. AKL has the animals as well as with the pool and the bus rides are not that different. Once you're taking a bus, does five more minutes really matter? Deluxe rooms are larger, too, something else to consider.

If your main park will be MK, I would consider the Contemporary or Bay Lake Tower over the Beach Club. Great pools (maybe not as great as Beach Club, but plenty of fun for kids), fireworks viewing, walk to MK or monorail, and less bus time overall than even Beach Club. But why stretch the budget if one of your other options fits? Of your choices, I would go with AKL, a more affordable deluxe with plenty of wow factor.