A child-friendly or theme restaurant would be great but I think as long as it is somewhere your child will like the food and atmosphere, it will be a great memory. When my brother was little he LOVED Chinese food, so our family tradition was to go to the same neighborhood Chinese restaurant each year. He has moved out of that area, but guess what he still has for his birthday dinner (30+ years later)? Yep, Chinese! Our family's celebratory restaurant for many years has been RJ Grunt's near Lincoln Park Zoo. It's just a place our kids grew up loving and so they often request it for their birthday dinner. My son actually loves breakfast food so he usually chooses somewhere he can get French toast. Or if your son loves pizza, go to a sit-down pizza place. Rainforest Cafe is fun too. And, while most of us adults hate it, kids do love Chuck E Cheese. He might see that as a special place for his birthday dinner plus playtime. And there will come a day when your kids don't want to go there, so it can be endured for a few years. Most of all - have fun!