For parties where we want to get there by 4, we try to do tea at the grand floridian around 2 or 2:30. Between the pot of tea, plate of sandwiches, and desserts, it's a nice size early dinner. Then we just snack during the party.
If we don't need to be at the party until 7, we try to eat at the wave in the contemporary around 5, and then walk over to MK. The wave is usually a substantial meal, so durung the party we just grab a snack toward midnight but don't need much before then.
If we're already in MK, we try to head to CHH before the party starts, usually around 6. That can be crowded, though.