Our DD was 2 yrs 8 months on our trip.
On the first day we did MGM (then almost 11 yr old DS's request)
She did everything she was allowed to go on (no TOT, RnR or Star Tours)
I don't think any of the rides bored her. The only shows we saw were Beauty and hte Beast and Muppets.
She wasn't frightened of anything but I could see kids being afraid of
Muppets (if the they are wearing the glasses. If so just take them off).
Little Mermaid.. it can get loud and scary. It is also very dark
The Great Movie ride. The Alien scene and the shoot out (mobster or wester depending on which section you get) could be scary.
The tours (back stage and animation) could get boring but DD really loved the animation tour.
AK
we didn't do tarzan rocks. We ran out of time. I have heard it is loud
the rest of the stuff she could do she enjoyed. The boneyard was by far her favoirte.
Epcot
I could see most kids being bored with WS but both or our kids love to shop and eat so it was a big hit.
The ride in Norway could be a little scary and so can HISTA
I think she liked the living seas the best here