There are not a ton of character dining options at the present time. When is your trip? How old is your son?
I have two boys currently 6 and 9---they have always enjoyed Ohana Breakfast (characters are returning soon with Pluto, Lilo, Stitch and Mickey) We also ate at Toppollinos (Mickey, Minnie, Donald and Daisy) for breakfast last week and they enjoyed it. We like the food at both of those places too, so that is a bonus for us adults. My oldest said he was a little past Chef Mickey's--he said it was too little kid-ish to want to eat there this time. It just depends on what characters you want to see.