My advice to you, as someone who recently tried to get night photos at Disney: Don't bother.
Any photo of acceptable quality is going to require a tripod; there will simply be too many people, all packed in too small a space, for you to get your camera set up, much less take an unobstructed photo.
Even trying to shoot hand-held, you will spend so much time messing with ISO and other settings that you will just end up missing the show and have nothing but a pile of blurry, poorly-exposed photos to show for it. Not to mention the inconvenience and weight of lugging an SLR and tripod around.
The photos you linked were most likely taken with special access, giving the photographer all the time in the world to take the shot -- you won't have that luxury.
I strongly advise you stick to a point-and-shoot, and just enjoy the show with your family.