Been here quite a number of times. Wether it be for Raptors, Leafs, UFC, WWE, or various concerts. It's definitely a great multipurpose venue. I don't think I have ever seen it empty. Recently they have improved the food availability and I must say I am quite impressed. Back in the day you would be stuck with the usual fare of pizza, hotdogs, chicken fingers or nachos. Popcorn and candy as well. Nowadays they offer prime rib sandwiches, sushi, Smoke's Poutine, and a bevy of other options.
Expect to pay a premium of course over traditional places to eat. After all you're there to see entertainment and the food is secondary. Parking is available beside the ACC but if you don't feel like paying $30 I suggest parking at nearby Esplanade or the Green P at University and Front.
No matter what you're doing to The Air Canada Center for you are sure to have a great experience!