Besides those rides, watch out for the 3D movies. If your children haven't experienced 3D before, you might be in for some fear at least from your older child. Despite trying to prepare her for it my 3 year old spent most of her first viewing of Philarmagic in my arms. (Simba freaked her right out!) However after that one, she started to understand how it worked, went back again and loved it, same with Muppets. Never did Tough to be a Bug though, she already has a big fear of bugs and heard from many that movie usually scares young children.
Every child is different, when I was young I remember being terrified of that talking skull on the top of the drop in PotC, but my daughter at 3 loves Pirates. (of course the skull is gone now!) She also loves stuff like BTM, but hates HM.