Not sure if you want to be downtown or not, but if you do, Brewers Alley is fun and has rooftop dining where you can watch Market Street. The menu is pretty broad so everyone should be able to find something. White Rabbit has great pizza, but I hate the ordering process with the QR code menu (they will bring paper ones if asked), but they get really busy during peak hours and the wait for tables is insane. Cugino Forno is the latest "hot" pizza spot, it gets lots of buzz on the Fredrick food social media scenes.
If you want something a little nicer than pizza, but not formal/fine like Dutch's Daughter/Monocacy Crossing, you may want to consider Fratelli's in Middletown, the food is great with huge portions, Italian and seafood but not super formal. You will need to call for reservations because they get really busy on evenings/weekends.
And, there is always Chuck E. Cheese on Guilford Drive (Since it's your son's Bday)