We "discovered" El Rio Del Tiempo in December 2000, on a very cold day, when we just wanted to be inside where it was warm until time for the evening show. We hung out in the China pavillion through several acrobatic performances, and then went to Mexico and rode El Rio Del Tiempo. There wasn't a line of people waiting to get on, so they just let us stay on, and we rode it at least 6 or 7 times. We have recommended this ride to many others since then, and they all shared our enjoyment of it.
Its a Small World is my next favorite - and I'm so happy it will have reopened by the time we get there in December - AND - that some of the new boats will be wheelchair accessible. My DD's financee will be with us this trip, and he isn't able to transfer out of his electric wheelchair. I have very fond memories of first seeing It's A Small World at the New York Worlds Fair - where I believe it was sponsored by Pepsi. So glad that Disney latched on to it, and that they're keeping it going - (even though that song does get stuck in the brain for weeks afterward).