I had a lot of fun a few years ago and stayed at Circus Circus. They had lots of fun rides and video games. We also did a lot of other stuff, like took a tour of Hoover Dam and went hiking at Red Rock Canyon and The Valley of Fire. A friend of mine stayed at Mandalay Bay over the summer and said it was great swimming in their wave pool. It is huge.
If you like eating, it is great too. You can go to a buffet and eat all the food you want and it is really good too. Just don't eat too much or you might get a stomach ache. Yeah, you will like it.