On a forum of Disney fans like this it is easy for everyone to say "more days is better!". You will have fun either way with 3 or 4 days. We have only ever done one four day trip and everyone thought it was one day too much - for us. But if we had not gone in 10 years then four days might have been more welcome.
Do you think it will be 10 more years until you go again? Then maybe four days would be worth it. If you think you will be back in a year or two then maybe three days will be right. Especially with a two-year-old.
I totally agree with you, HydroGuy. I think, Ashpinoza, if you don't foresee being able to get back to DLR for a long time, then take the extra day and make it a 4-day trip. You can space everything out so that there are nice rest periods for the little one and no one has to feel rushed or overwhelmed. Also, I don't know how interested you are in the 'noticing the details' aspect of things, but that is something some folks like to do when they have extra time - they just kind of wander around at a leisurely pace and take in all the little hidden gems and out of the way nooks that you may not get to see in a typical, hectic, fast-paced day at DLR.
But, if you plan to be back to DLR again very soon, I think you could get away with 3 days. With my group of friends, and we don't have any kids, they are at an age now where they get their fill of DLR pretty early on in the day, and either need to take the mid-day rest breaks to recharge the batteries or only stay in the parks for a few hours and leave altogether. They get impatient and tired sooner than I do Because I like to take in all the wonderful details as well as try aimlessly to kick my friends' butts on Toy Story Midway Mania, for me a good trip would be a 4-day trip, where I could spend two of those days with them, enjoying all the rides and character meals, and the other two days solo, where I could look in any shops I wanted and stop to take any pictures I wanted, without worrying that I was making someone wait on me. I have had long chunks of time away from DLR in the past, and so much changed during those periods that I feel I need to soak in everything I can now, just in case I have to go for another long block of time without being able to go to DLR.
So I always thinks
more time at DLR is better if you are not going to be back there again for a long time, but if you think this will be one of many trips in the near future, then 3 days should be okay.