Hi petunia,
We're Canadian as well, so I can give you our list of favourite American chains that we try to hit while we're in Orlando:
For dinners, we love Olive Garden, TGI Fridays, Chili's, Golden Corral, Giordano's, Cracker Barrel, Cici's Pizza, Buffalo Wild Wing, and Friendly's (Friendly's is also a suitable pick for lunch....long as you are hungry enough for ice cream!!).
Good for lunches are Steak & Shake and Sonic Drive-In. We have also enjoyed Checkers (super, super cheap) and Popeyes Chicken (yes, we have them in the larger centres here in Canada but none near our home, so its still a novelty).
Some "themed" or kid-centric dining that we've done (and enjoyed) are: the World's Largest Playplace McDonald's (on Sand Lake Road just off I-Drive....they have a special "Bistro" menu in addition to the regular McD's fare), Shrek Feast at Gaylord Palms (breakfast buffet at Villa de Flora which features Shrek, Fiona and Puss In Boots), and NBA City (at Universal's CityWalk....we have a basketball fan in the family).
I have heard great things about Millers Ale House. We aim to try that one in August.