I think you have the right idea, rent an RV for a 3 days.
Here's a good way to think of an RV. Think of an RV as an extension of your stick and brick house. Think of it as an extra bedroom, or an extra office, or an extra entertainment room. If you can park it at home, you may find yourself using it a lot this way, and camping too.
I think you are wise in making your first experience a short one. The only problem is, you'll need to stock everything. Blankets, sheets, pillows, dishes, any kind of entertainment you enjoy, games, activities. Then your food, toiletries, and everything else you may want to bring.
Then when you are done, you need to empty it all out to return the rental RV. So, to keep cost down, use items from your home, don't purchase anything new specific for the RV or for camping. You already have everything in your home.
When you purchase your own, and you don't have to unload anything any more, that's when you start purchasing items specific for the RV and camping. If you do it this way, you'll make the experience a lot easier on the check-book too.
A shorter drive for your first experience is a good choice too. And when you get to your camp site, take a little time to just relax around a campfire a while and enjoy the moment and the down time.
Plan your activities, but don't hold yourself to them. If your plans change, that's perfectly OK. Spur of the moment events are really the most memorable and those are the things you'll be talking about for years to come.
I think you are on the right track. You've making a sound decision here. As stated above, get the wife involved as much as possible. The more she has ownership of the trip, the more she'll like everything. That's how you win them over! (really!).
Good luck and keep reading and checking up with these forums. There's a wealth of information and tips on these pages that folks write about.
Happy Camping!
