The Oasis RV Resort is a great place. We stay there every year. It is located at the south end of Vegas on the east side of the 15 Fwy across from Bass Pro Shops.
They have an adults only pool if you don't want to hang with the kids at the family pool. A lounge, cafe, gym and so on. We love to set in the white sand beach area, in the shade with a rum & coke and complain about the heat......it's hot, I need some more ice...:-)