I swear by the Skechers Go Walk shoes. A friend got them before her first Disney trip last August, and wouldn't stop raving about them, so I got a pair to try out and fell in love. I wore them to work (retail, so a lot of walking around) for about a month before my trip in January to get them nice and broken in, and they were great.
Ended up buying two other pairs so now I have two pairs of the sneaker Go Walks, and a pair of ballet flat-style Go Walks and they are all amazing. They come with me on every trip and have not failed me so far.
On my Disney trip I wish I had extra pairs because I could have done with rotating them, but overall my feet were pretty happy.
I have done Disney in Keds, Vans, flip flops, kitten heel boots, and those giant red and black Mickey Crocs, which I bought one year in the middle of the day because my shoes DIED and I could not walk anymore in them. The Go Walks win hands down.
I have tried the Skechers with the memory foam and do not like them. My feet are wide and the pair I had were already kinda narrow, and after a busy day of work where I was running around a lot, they got so tight that I got INSANE blisters on the tops of my feet. The memory foam was super comfy but the actual shoe was horrible.
I do have Nike memory foam sandals and really like them, though. But I have not worn them on long walking days so I don't know if they would be good for Disney.