We just did Disneyland both from the RV park and from a hotel (while the RV had some repairs done).
You can't beat the convenience of location if you get a hotel right near the Disneyland entrance. You can walk to the parks (saved us $17/day in ART/bus costs). BUT- the nightly rate is way higher (3 to almost 4x for me with staying at a Marriott). There was no kitchen in the hotel that we stayed at, so our food costs were higher. Our hotel had a small pool. The neighboring hotel had a whole little water park- decide if that's important for you. We paid extra for a "themed"-room and it had some Cars stuff on the walls. It gave you a nice Disney feel, though I'm not sure how much I would pay for that again.

The view of the fireworks from the balcony was really nice:

Walking, you won't be alone at the end of the night:

You'll always have the age-old argument of hotel vs. RV park.
We then moved over to the RV park once the camper was done. The RV park is strangely situated off of city streets. There is no concept of security/no gate/no nothing. We didn't have any issues, but it was different than what I'm accustomed to. The park has spaces for big rigs down to little guys. We were a little cozy on our site with a 42' fifth wheel + 22' truck- mostly with parking the truck and making sure we weren't hanging into the campground road. Taking the ART (bus) was $17/day for us because we didn't buy multi-day passes. The walk wasn't realistic for us, though I read others do it. I wouldn't drive + pay for parking, even if it was cheaper- the drop off for the buses was very convenient to the hub between the parks.
The view of fireworks from the campsite wasn't bad either:

Our campsite:

We didn't use it, but the RV park had a small pool. And the laundry facilities were decent, though only a few machines per building (we ultimately had to spread our laundry across machines in 2 buildings on laundry day).
Other sites were pull-thrus and had parking behind them for trucks:

ART fares when we were there:

*Double check the route # when you're there. The sign at Disney was wrong and we went on a joy ride with a driver our first trip home.