whenever my husband gets cranky in epcot, we'll visit the american adventure (he'll awake all happy & refreshed...) - at mk, it's 2 or 3 times around on the TTA (takes his sneakers off & stretches out across the seats) or a seating at the hall of presidents (he's usually snoring before the curtain opens....) and at mgm, we'll stop in at the sci fi dine in for a snack for me(and a nice nap for him, there in the dark)
he'd probably sleep during spaceship earth, except the headrest in those seats is kind of hard & makes it difficult to relax..... otherwise, the cool, darkness during the ride helps him get back to his "happy place"