I'll repeat Losvu's question. Why Vegas? By that I mean, there must be something that's motivating you to consider coming to Vegas. One spouse attending a convention? Some family event? A visit with friends or relatives? Or, perhaps you just want to sample the (mostly adult-oriented) pleasures of Vegas. Something is causing you to consider going to Vegas. That will influence any recommendations.
Specific dates are important, too. Rates on Friday and Saturday are double or triple other nights. Rates change from week to week.
Vegas is OK for kids. Not great, but OK. But it has to be about the kids, not you. That's really true regardless of where you go, when you have small (or not so small) kids.