Honestly I went at 32 weeks pregnant and then we took her when she was 13 months old. Anything I could do pregnant I could do with her. The only things she couldn't do were rides with height restrictions. I always loved Disney, but going pregnant and with a baby just made me realize how it truly is a "family" destination. Off the top of my head the things we couldn't do were Kali River Rapids, Dinosaur, EE, and Primeval Whirl at AK. At Epcot it was Soarin, Mission Space and Test Track....MK was BTMRR and Space Mountain and then Splash Mountain.....and Disney Studios was TOT, RNRC and Star Tours.....we still haven't braved Sounds Dangerous since DD (now 5) has a very vivid imagination. She has however done Haunted Mansion since that first trip.
We still haven't baby swapped....although I hear it's an easy process. We have just always enjoyed everything as a family.
We did go back for a nap every day. DD was too caught up in everything that she wouldn't sleep in the stroller and we had the big, bulky one (that is one thing I would suggest is to get a lightweight stroller - we got a Mac Quest after that first trip and LOVED it). I was still nursing her then so that was easy, but when we ate she would just have a little bit of whatever we were having.
The one thing that helped us.....and it isn't practical every time.....is that we got annual passes. We went December 2004, September 2005 (we threw this trip in just because we had ap's and friends asked us to go with them) and December 2005 so with two trips planned it made sense for us. But what I really liked about having ap's is that I never felt like we were "wasting" tickets or money if we needed to leave the parks. We completely went off her schedule. If she was tired we left....if she was cranky we left......HOWEVER, with that being said she did a great job and it was an amazing trip.