So my sister-in-law moved to Long Beach (apparently there isn't as much drama there as Snoop would have you believe...) and my wife, son and I are planning to do a road trip out to visit and spend Christmas with her and her husband. We'll be taking I-40 but we want to have a somewhat leisurely trip out so we can see some of the country. We're planning to leave with roughly a week to get there and I was wondering what National/State Parks or natural landmarks I should make time to see. We're not wanting to go drastically off course, but we are definitely swinging by the Grand Canyon either on the way there or the way back and we're willing to take a little time for any other "must see" spots since there's no telling when we'll be able to make a tip like this again. Any suggestions for awesome stop offs where we can camp during the trip or must see "leg stretchers" for daytime stops?

THANKS!