If you don't know the difference between a Class A motor home, a fifth wheel and a pop-up, well, it's time to learn.
If you want to navigate the Mojave Desert or pull up next to the shoreline of a lake to hear the lapping waves at night, the Class A motor home -- which generally exceeds 30 feet (9 meters) in length -- is not the right choice for you. This is a vehicle for hitting the highway in style, and definitely not the vehicle for off-road adventures.
If you'd like to park the RV and then drive a truck around town with greater ease, then the fifth wheel might be a good option. The fifth wheel detaches from the truck that tows it.
If you'd like a genuine camping experience, with a tip of the hat to times gone by, try the pop-up trailer. This is generally an option for a long weekend, not a three-month excursion down the Pacific Coast, but for a quick trip to the mountains or the lake, it's a great way to feel the outdoors without necessarily eating out every night or sleeping on the ground.
In short, match the vehicle to the kind of trip you want to take. The longer you're gone, the more appealing those conveniences of home might seem.