At MK, if you are standing near the front of the crowd, really close to the train station or even underneath it, you won't be able to see the train above you for the opening ceremony. But then you will be able to be one of the first ones in, so it's up to you!
At EPCOT in Dec, there was a double-decker bus (from the U.K.) full of characters. I don't remember exactly, but I think they drove up to the main gate, waved, and sang a song.