Simba's Circle of Life is pretty cool.
I wonder if it would be possible to make it more "interactive" or "4D". If you've ever been to Universal Studios and done hte Harry Potter Experience ride, basically you sit in a sideways car about 4 people deep. You are strapped in because this thing shakes and twists and turns etc to give you the feel of actually moving with what's happening in front of you. I.e there are parts where you dodge a dragon while Harry on his broom races just in front of you. Wind and water blows in your face and the ride moves and tilts you enough to trick your body into thinking you're moving like the screen is showing.
That's obviously a simplistic explanation, but if we could pull someting like that off with all of the awesome parts of the Lion King, i think it would be a huge hit.
And for the people in line, could do something like the old school star wars ride did back at Disney or the old Disaster Transport at Cedar Point (before they scrapped it), where you have stuff going on in the line room, Screens playing messages and conveyors moving random stuff. just things to get kids interested in while they wait.
that's a link to a rather long video with all the Harry Potter parts of Universal.