An all in one experience. It's the House of Blues.
The House of Blues is best known for being a concert hall, but you can get a bite to eat or down a few cold ones all the same. I've seen Boogie Nights (a bitchin' 70's cover band) here and it was a blast. The floor is spacious and can accomodate hundreds. Opposite the stage is a bar and a couple of levels for people to hand out and watch if they don't want to be in the middle of the crowd. However, some of the watching space, especially right in the middle in front of the bar, is for VIP seating. Drinks are typical Vegas pricing. You are inside the Mandalay Bay after all.
On a separate occasion I grabbed lunch at the restaurant. It's in a portion totally apart from the concert hall. Mix of booth and table seating. I got a burger and beer. Quality of food and service is good, but nothing extraordinary. Set me back around 15 bucks, so you're not breaking the bank by any means. It's also family friendly place.