Zion National Park, take shuttle or drive?

Take the car and drive yourself. I drove myself there from Vegas and stayed in St. George, Utah on the trip. I went in January, so some of the roads were closed in the park but there was enough open to enjoy the place. Much better to drive and go at your own pace. Plus, it might be hard for your parents to get onto the shuttle depending on their health. Zion shouldn't be that busy the beginning of November so better to drive it. Beautiful place. Hope they enjoy the trip.