I agree I do not like Roller Coasters. I have not ridden the new Barnstormer coaster--I rode it once with my niece a few years ago, but I do LOVE LOVE LOVE TM. It's my favorite ride at MK. I am an annual passholder and there are only a few rides I haven't ridden (Sp Mtn, RnR C, Exp Ev, Mis Sp, and Tow of Ter), but I will ride TM. I just think it's a fun little coaster. It has three lifts. If you want a "slower" ride, try to ride up front if they will let you. The first couple of cars appear to go slower because you are halfway down the drop before you take off when the rest of the train goes over the drop. Personally I like the last car or the car in front of that. That is my favorite place to sit.

Also when you go up the hills lean forward in your seat until the cars catch up. It will help from getting your back/neck dislodged.

There is a "catch" I guess you could call it when go up the hills...and these hills don't feel like they are big. I do not like heights (get dizzy) and I think these are okay hills. Anyway, just passing some helpful info if you decide to go.
PS This is my first post and hopefully it's helpful.

(I don't know all the abbreviations yet.) All in all, if you don't want to go on it just wait until the other person gets back. I do it all the time when I don't want to ride a ride that day. They ride and I'll hang out at the end or go to a store and come back (or go get fastpasses for another ride). Oh, another thing you can do is both of you get a fastpass and other person can ride twice. My dad will do that for my mom a lot since he doesn't ride many of the rides.