We took a 4y and 9 mo old in Jan, and you'll be surprised at how much they can do. We took the baby on pretty much every ride without a height requirement, and he did just fine. My 4 y/o is tall for his age - he was 43" at time of travel - and he enjoyed Splash and BTMRR. He rode Barnstormer for the first time when he was 2, and made us ride 3 more times in a row he loved it so much. 7DMT was deemed "too scary" this last trip, but he still rode twice. Both kids have liked TSMMM on both visits. We skipped ToT, RnRC, and Space Mtn. Hubby and I took turns on EE via single rider line, while the other waited with the kids in the Boneyard (playground). TT was his favorite ride of all, and he can't wait until we go back in a few months to ride it again. We did Soarin' as well. He got to ride every height requirement ride twice, since we utilized rider swap. This was a big perk for him, except when we made him ride 7D twice, haha. On our first visit, when he was a young 2, we learned that he didn't like dark rides. PP made him cry, and he wasn't even a fan of Pooh (except playing in the queue). Other than that, I think WDW's height requirements are a pretty good gauge of what's going to be appropriate. Obviously all kids are different, but as long as you are a little flexible if they don't like something, there's no harm in trying!
