My son is 11 and has never been on a real roller coaster. Yeah he's been on a few at the fairs that come to town but we've never been to Cedar Point or Six Flags or on any serious roller coasters. So, when we went we went to Disney World and he exclaimed to all the world that he wanted to ride all the big coasters he could I could only smile.
I remember my first coaster experience vividly. It was when the Corkscrew was the king of coasters having the only double-inverted loop in the world at that time. After bragging to everyone how I was going to spend the whole day riding that beast, it becomes a different story when you are confronted with the sheer size, speed, and g-forces involved. Yeah, I rode it. Once. Vowed to myself never again (broke that promise a few times but can't say I ever enjoyed any coaster).
Flash forward to 2010. First day is Animal Kingdom. We ride a few coasters and luck out when we get to Expedition Everest as the wait is only 15 minutes. We ride it twice. It's claim to fame is a twisting backwards drop through pitch black then some tight forward turns to finish. Thrill level middling and my son came out of it ok. Thought it was cool but the video evidence ( they snap your picture at one spot ) showed definite fear.
Next Day is Magic Kingdom. Some cool rides here, Thunder Mountain and Splash mountain were good middlin coasters. Saved Space Mountain for the end of the day. I had been building this one up for weeks, telling my son tales of when I was on it 20 yrs ago. The whole ride is in the dark. What I had forgotten was that you actually sit single file in a tiny, tight little sled-like thing. My son started making sounds about going back down. My own mouth was dry as sand (I knew what was coming).
John Wayne once said, "Courage is being scared to death, and saddling up anyway". Both of us stepped on without backing out. I had to get the very front seat, of course. Now Space Mtn is not a very scary coaster, per se. No inverted loops, all forward motion, speed is somewhat slow. But in total darkness, getting whipped about with no idea a turn is coming, and constantly thinking something is going to whack you in the head; its not exactly a walk on the beach either.
Next day, we went to Epcot. Neither one of us mentioned coasters.