We went for three days in March and we did half days at AK and MGM and full days at MK and Epcot, which worked well for us. It really depends on what you like to do the best and if you have hopper passes. Also use fast pass as often as you can to get the most out of your precious time. Here are my list of must do's at each park:
MK- Space Mountain,Small World,Splash Mountain,Pooh, Dumbo,Country Bear Jamboree,Peter Pan,Haunted Mansion.
Epcot- Spaceship Earth,Test Track,dinner at Le Cellier or Biergarten,strolling around World Showcase,Illuminations.
AK -Festival of the Lion King, Kilamanjaro Safari,Primeval Whirl
MGM- Beauty and the Beast Show,TOT,Millionaire,Fantasmic.
Have Fun!
