A lot depends on what you want to do..
I have spent eight days at Disneyland with my heir apparent on one trip. It was a great feeling, not worrying about having to rush to see something before the lines make it unbearable.
The relaxed attitude is what makes Disneyland trips so much fun, in my opinion..
But, if you're crunched for time, I have found that three days gives you the minimum amount of time to see everything in Disneyland. Any less and there will be rides not ridden, shows not seen, food not eaten...
