Don't automatically assume epcot isn't for toddlers. My son has always loved it (10 mos, 24 mos and now at 4 it's still his favorite)!!
I, personally, and especially with a kid, prefer world showcase earlier in the day. By the evening, it's just too crowded for me, especially when pushing a stroller.
There is a ton of kid friendly stuff there.
Like a pp said, my son has a fascination with spaceship earth. The seas with nemo and friends is fun. My son thought the Imagination ride was okay, but played for a good hour with the music stuff after the ride.