Soarin absolutely brought out my fear of heights, my hands started to sweat so much I felt I couldn't hold on (and I was first seat, first row). But, then my sweet DH said very calmly, just look up to where you can see the ceiling line to remind yourself you are simply sitting in a room. Once I was able to do this, I began to relax and it ended up being one of my favorite rides. It really is breathtaking and certainly the closest I will ever come to hangliding!
Thunder Mountain Railroad never bothered me at all, it's one of my favs. I was so panicked I barely remember Splash Mountain (except once again, I ended up being in the first seat - but I survived). I'm going back in July and DD is trying to convince me to do Space Mountain and TOT.
Thanks for bringing this subject up. I'd love to hear about other height fearers reactions to these rides.