One of my worst memories was our very first trip with kids, going to MK the afternoon of our arrival, the Wednesday after Easter. Standing in Fantasyland at 2pm I was practically in tears. I had left the DD's with my husband and went to every ride a 2 and 4 yrold could ride that had FP's. Every single FP was gone except Pooh which had a return time of 8:30pm. The only ride we rode was IASW before we went to our 5:30 PS. There was a CM standing on a stool in the middle of the walkway between IASW and Peter Pan trying to direct the stroller traffice. It was quite comical. It was a complete traffic jam you couldn't move.
I was a complete newbie to Disney, and it was before discovering the The Unofficial Guide, Passporters and all of the good people on these boards. All I knew was what I had read from Birnbaum's which I still love to read but isn't helpful with touring plans. It was a complete shock to me that the line for Dumbo was all the way around the Carousel.
We still go that week (except this year) but planning makes all of the difference and having more realistic expectations.