I stayed at Circus Circus not because I'm into Circuses, but because that was the hotel that went with the airline package that allowed me to stay in LV for $135 including airfare.
It's at the far end of the strip, right across the street from the Riviera (which has *THE* best buffet on the strip, in my opinion).
The room we had was VERY large and spacious and had 2 king sized beds in it and overlooked the desert. The staff was very friendly and accomodating.
The theme park part of Circus Circus is interesting. There's a roller coaster and other rides and it's all inside this big pink dome and when the light shines through everything has this odd color to it.
Many restuarants, although I would reccomend going to the Pink Pony after midnight when you can get a breakfast special for very cheap. The signs advertising this special are all over the hotel---HOWEVER, when you get to the restaurant, the special is NOT LISTED ON THE MENU OR ANYWHERE ELSE IN THE HOTEL---so you MUST ASK FOR IT SPECIFICALLY or else they'll charge you menu price.
All in all, a very nice place to stay and definitely for those who have kids.