And you should know that if you fastpass a ride, you cannot get another fastpass until after the first ride -- meaning plan carefully. At busy times, I have seen fast pass 4+ hours or more later.

Also, utilize the single rider line whenever possible -- it usually moves pretty quickly. If it's two adults and a three-year old, you will have to do the baby switch anyway, since the child will not be allowed on some of the rides.

Another suggestion is to get to the big-crowd rides during parade times, especially in the Magic Kingdom. Most people know this trick, but it is usually a little faster at those times.

Check for an e-ticket night while you are there -- these are special nights offered to Disney resort guests -- for usually $10, you can stay in the park a few hours later -- only the big-crowd rides are usually running. You could check with your hotel before you arrive, and plan accordingly -- take the 3-year-old back for a nap in the afternoon when lines are longest and stay later in the park.

Have a great time -- Christmas at Disney is beautiful.