We had a similar problem on our sons' first visit. They were 6. We started at MK, went over to Tomorrowland, saw a long line for Buzz and grabbed a FP. Said look, that "stitch thing" only has a 5 minute wait, lets do that....the boys love Stitch. OMG had no idea about that attraction and the boys freaked out. Hated the touching, the spitting, etc..... In fact wouldn't go in that attraction again for years....LOL So after promising that we wouldn't go in there again, we next go on to Buzz and they seem fine we explain the ride to them...shoot the Zurgs. Half way through the line, one son is having a hysterical melt down. We asked him what was wrong. He's crying that he doesn't want to die. What??? So in his mind if Stitch spits at you Zurg must shoot back and he was afraid we wouldn't survive. LOL I calmly and quietly explained to him that it would be pretty bad for business if Disney killed guests and that the ride was just pretend. Fake guns, just targets, just like a video game. That satisfied him. They were a little leery of other dark rides on that trip but we just played the "real or pretend" game in line. If they loved something, of course it's real. If they were scared, it's just pretend so nothing to worry about. Haunted Mansion was OK, but they only agreed to try once that trip. Roller coasters great. They only thing they refused was riding TOT because they weren't going on anything named Terror!
regards
regards