Personally, I think 4 is the best time, they aren't in school yet, and everything is real to them, so the magic is real, and they are just in awe of everything. We are trying to bring each of our kids when they are 4. Next time our youngest will be just 5, but I think it will still be fine. Last time we went our oldest was 7 and it wasn't "magical" anymore, she knows the characters aren't real. And my daughter who is 6 also knows they aren't real, and has known for a while, so I feel like it is really important to hit them when they still believe.
In regards to remembering it, I went to Disney World twice as a kid, once when I was maybe 7ish and once when I was 11 I think... I don't remember a thing about either time. If they are having fun at the moment, and you take lots of pics, it will be worth it.
In regards to remembering it, I went to Disney World twice as a kid, once when I was maybe 7ish and once when I was 11 I think... I don't remember a thing about either time. If they are having fun at the moment, and you take lots of pics, it will be worth it.