In Future World, I would say Living With the Land or Spaceship Earth depending on my mood. Turtle Time with Crush is more of an interactive show, but it also ranks high. Current Soarin' is a pale comparison to Soarin over California. Test Track is a pale comparison to Radiator Springs Racers in DCA. I do not like Mission Space, not because I get sick, but because it is quite boring, I almost think it would be better to not have you push any buttons at all. Nemo is cute but nothing special. Journey into Imagination is meh.
In World Showcase, I would have to go with Grand Fiesta Tour, not so much for the ride, but for the whole Mexican pyramid. Frozen is fun, but it's just not worth the lines. All the 360 movies are ok. That beauty and beast movie is fun too. American Adventure is a nice way to rest.
I assume once Ratoutille and GOTG are availble, my votes may change.
Honestly, the best part of Epcot is just walking around the world showcase, and exploring.