My DD7 is very afraid of rides. I talked her into Barnstormer and she was terrified. She won't consider any other coasters. These are attractions that she likes:
MK: Carousel of Progress, People Mover, Speedway, Monsters Inc, Buzz Lightyear (this is actually a fairly new one- she was afraid of this one for a while), Dumbo, Aladdin, Small World, Country Bears, Pirates, Jungle Cruise, Swiss Family Tree House, the Train, the tea cups (She does not like Pooh because of the bouncing Tigger part but she will ride it; she doesn't like Peter Pan either.)
Epcot: Spaceship Earth, Ellen, Mexico, The Land, Soarin' (she gets scared at take off, then is okay), she likes the Nemo aquarium but not the ride (She didn't like Maelstrom and doesn't like Frozen because of the backwards part.)
DHS: Indiana Jones show, TSMM, Disney Jr show, sometimes TGMR but parts of it scare her
AK: Safari, walking trails, Rafiki's planet watch, Lion King show, dino dig playground, Wilderness Explorers scavenger hunt game
Every kid is different, so it's hard to say exactly what yours might like. I would definitely not try to push him onto things. It's not worth it. DD tried a kiddie coaster at Legoland and sobbed for ten minutes on a bench afterwards. I felt horrible.