One challenge with kids is making sure they don't get too board. We have some cool things that can help entertain your little guests. Bubble machine - They are always a hit with the kids. If they are going to blow them on the dance floor you will want a responsible DJ that will make sure the floor does not get too wet.
Another great one we have seen is at the hall a "Kids Section" This can be a table along a wall or as much as a complete closed in area (not far from the festivities). Supply it with coloring books, crayons, maybe even glue and gems (check with the location before bringing glitter.) Funny glasses, a couple games.
If you have lots of kids either during cocktails or after the main dinner, like when head table is done eating, have the DJ keep the volume lower, yet play music for the kids. They will be dancing and having a good time, and you just bought yourselves 30-45 minutes to say hi to all your guests.
If you have outdoor space that is even better. Then you can get jumbo games, Jenga, Checkers, maybe some corn hole and ladder ball. The adults will enjoy it too.
One we did when our kids were little is a portable VCR/TV; of course now it can be as simple as a couple of tablets with couple kids movies loaded. You may want to hold on to these until later in the evening when the adults want to dance.