Marty - the color on your shots above is amazing - we don't see that kind of color here in the desert. It really makes me want to get up north for color...

James - you will be fine in Zion as long as your family can ride the shuttle. You can make a whole day of riding the shuttle to a stop - getting out and walking a few hundred yards at fantastic scenery, and going to the next stop. It is really nice.

For longer hikes follow the river trail like Tucson Jim suggested. It is flat, wide, smooth walking. Even the trail to the start of the narrows is wide, flat and fairly level for over the first mile.

Have fun.