We got the Chicco all terrain umbrella stroller for our 4 1/2 year old 42 inch 38 # daughter and LOVED it - I think it was $40 or so at Babys R Us. It's an umbrella stroller w/a shade on the top and a small footrest. No storage or tray, so we got a net bag and clips for the back and a cup holder that we attached to the side. We also clipped a $5 batter-operated fan on , it worked out great for us. We use the stroller at home and plan on taking it next week to Disney also - she's now 5, 44 inches and 41 #s. If she feels like walking I just toss my backpack in the stroller. I think it depends on the child on whether to get a stroller; for us, having our own was definitely the best - she rode in it to and from the bus (where we wouldn't have had one if we rented) and always had a seat while we were waiting, and then got to ride the hike back to our hotel room.
Good luck!!
Good luck!!