I have been to DW twice with young children. The first time was Sept 05. I went my DH, Sister and BIL and my 20 mo old daughter (and I was 5 months along with my 2nd). My DD had a great time and so did I. Of course, MK and AK were her favorite parks, but she also loved Playhouse Disney and the parade @ Disney Studios. Every morning she would wake up and ask if we were going outside!

(The only thing that my daughter didn't like were the characters. They scared her, but only when we were close to them--she loved watching them from afar. So we just kept our distance.)
The second time was Sept 06. My DH and I went with my MIL and SIL. Then my girls were 2 1/2 and 8 months. They both did great. Disney World is so visually stimulating, my baby loved it. It was really hot, of course, and she still did great.
We got up early every morning and were at the parks around the time they opened and then after lunch we went back to the hotel and rested (during the hottest part of the day) so the girls could nap (a definite must!!) Then headed back to the parks in the evening. Everyone had a great time!!
I'm sure you know they have the parent swap in some lines where you can have one adult ride while the other waits with the kids.
I never felt like I was doing a lot of work (no more than usual with two young kids). I had a great time, in fact, we are going back this December!!
Having said that, I did do a lot work ahead of time. Planning out our days--which park on what day and where and when we would eat. Eating earlier--lunch around 11:30 and dinner around 6:00 is a good idea too b/c the restaurants aren't usually too busy yet which means no waiting for a table (which is always a plus with little ones).
I don't know if any of this was helpful, but I hope so.

Enjoy your vacation, wherever you decide to go.
