Definately take the drive up through Monument Valley. If you wish there is a campground at Momuent Valley (Gouldings or something like that). Well maintained red earth and the only CG in the area. Really no reason to camp their unless you want to spend a wonderful day touring the Valley, Indian guides required. I have stayed at Aspen Rose in Durango three times over the years and enjoyed every visit.
Durango area can be pretty full when it comes to RV parks. I'd recommend booking now if your plans are solid enough. I haven't stayed at Alpen Rose but went by it last year & it looked nice. It was solidly booked. Back in April I booked some time there for this August.