We are headed to Disney early next year for 3 days. We are going to MK, EP, HS. I have 2 year old and a 4 year old that scares easy. What rides will they be able to do at those parks so I can plan according. I also have a 9 and 8 year old too that we have to find stuff for them to do as well but they get scared too.
At MK I would avoid Stitch's Great Escape. Forgetting that it is horrible attraction in general IMO, it is in the dark and has one of those harnesses that you pull down over your head which just compounds the fear factor for those that scare easily. On our first trip my 4 y.o. niece tried to crawl out from under the harness. The ride really upset her and my DD who was 6 at the time.
I'd also think twice about Mickey's Philharmagic. It is a 4D movie musical attraction. I love it! However, I don't think I've ever been when the 4D effects haven't caused a child to start crying. They are nothing scary, but for little ones being squirt with water or having air puffed in their face can be upsetting. It also tends to be pretty loud which can be upsetting for little ones. Most of the water and air puffs occur in the first couple scenes as I recall. The 4 y.o. might be okay if you talk about what to expect up front.
At DHS, I might think twice about Star Tours for the 4 y.o. It isn't particularly scary, but it is jerky. However, if the 4 y.o. tries the roller coasters at MK and likes them then ST should be no problem.
The 8 and 9 y.o. might have issues with Rock n Roller Coaster and Tower of Terror. (and the 4 y.o. if they meet the height req.) My DD was not much of daredevil where rides were concerned until she hit 10, however she did ride RnRR with no problem when she was 8. It is an indoor looping roller coaster. It is in the dark though, so she had no idea she went upside down until I told her months later. Had she seen the loop upfront she never would have ridden it. ToT...well the name says it all. My DD(12) finally came to like it in the past year. She wouldn't even try it until she was 10. I love the ride, but it really is terrifying.... in a good way.
It helped my DD knowing that while it feels like the car is falling, it actually isn't. It is being pulled down.
At Epcot the only thing I might be wary of is Mission Space (green) for the 4 y.o. because it also has a pull down harness. The ride itself isn't particuarly scary and there are all sorts of fun buttons to push! If the 4 y.o. knows what to expect with the harness upfront, it might be okay.
As the pp said, just start with milder stuff and work your way up.