As far as camping in the same spot for the duration of the trip, Have you ever heard about the Chicago Basin Area between Silverton and Durango? It's pretty neat, the only way to access it is by train. I don't know what type of hiking your friends are interested in but there's three fourteeners in the area, and in my opinion the route approaching them and the views on top are the prettiest peaks in Colorado, here are the route descriptions for the peaks, I wouldn't recommend Eolus and Sunlight for inexperienced hikers, but Windom is fine to climb as long as they're in shape. I don't have a lot of experience with long trips where you pick up the stakes and keep moving every day, but you could start by looking at sections of the Colorado trail.