Archview is a nice place but their store hours are crazy. It is the closest to Arches NP, just up the road (5min). It;s a fair drive into Moab from Arches.
We found the place friendly and easy to deal with and the veiw from there is very nice.
While Arches has no hookups they do have some very very pretty campsites. If you boondock I would stay there for a few days too.