There is info on the hotel's website that states how to call the shuttle. If you don't see it on the website, call the hotel ahead of time and ask them for the phone number you should call when you need the shuttle.
There is a lot to do there other than shop. There is an amusement park in the center, a good sized aquarium, and there are event spaces where there is usually something going on, and other things like Fly Over America that my kids loved. I don't know if you could make an entire extended weekend out of it, but you can sure make a day of it.