It will be a great time to visit Mesa Verde! I highly recommend making a reservation for a tour of the Cliff Palace where you will get to go into the dwellings. I would note if you are afraid of heights this may not be for you. There are many hiking trails to see from a bird's eye and across the deep canyons.
I can never recommend the train enough! This is a Durango staple. You will see beautiful scenery along the trip and a fun way to spend the day. I would recommend getting your tickets ahead of time.
Take a soak and relax! This is a great stop with pretty views
This is a great location with ziplining, axe throwing, rafting trips and off-road trips.
A fun and interactive museum and live fish hatchery!
It's September.. the trip to Silverton is going to be AMAZING for peeping those fall colors. Take the train or drive over. It's worth it!
The wedding will be close to closing day for the Bar D Chuckwagon but if you want the Western experience I would get your tickets to the dinner and show! It is across the river from the wedding venue. It is a beautiful place and there are a lot of activities for the kids.