Ah, good points Ron. Our friends who visited us at Moab for a few days last year didn't want to go off-roading, so we took them to Arches National Park for an easy, relaxing day trip and picnic. It's easy to get to from the campground, and is paved road all the way. Great scenery the entire trip. I'll get a few photos uploaded for folks to see.
Haven't been to Canyonlands, but will make a point of going there this upcoming trip.
I should also clarify that there's a wide variety of off-road trails around Moab, ranging from bunny runs to "no way!" Our trailblazing leaders let folks know ahead of time the difficulty and estimated duration of the trips.