Monterey Dunes Nice park, not too far from the Aquarium, but not walking distance, and right next to the beach. You can't see the ocean from the park as there is a mountain of sand dune in the way, but it's an easy walk to the beach. Oh yeah, and this place is pretty expensive. Last time I was there it was about $75 a night.
There is also a KOA at Moss Landing which is further from Monterey. It's a fairly small park with small spaces, but I like it. It isn't cheap either.
There is and RV park at the Monterey fairgrounds too, but I've never stayed there and there is a County RV park at Laguna Seca Racetrack. I stayed there once, but I prefer being closer to the beach.
Monterey is not really RV friendly. There are just not a lot of RV parks in the area. Don't be fooled by Monterey Vacation RV Park. Even though they have Monterey in their name they are over 30 miles from Monterey and they are right on Highway 101. I've never stayed there and I wouldn't because of the location, but I've seen others on here comment on it and they seemed to like the place.
I'll let others with more experience comment on the other areas.
