I suggest looking for a car rental agency near your lodging. You can zoom in on google maps and then search for rental cars. The airport is not that convenient for a large group with luggage. We returned a car to CDG one time and took the (crowded) RER into Paris and then walked to the hotel, I don't think it would be easy with five people.
After picking up the car, take the shortest route to the ring road. Just don't cross through the center and with GPS it will be easy. Then the drive is all very nice highways.
Be sure your rental car has enough room for everyone and your luggage, cars are usually quite small and have manual transmission.
Enjoy the trip!