OK, so hearing no suggestions I did some serious research and came up with the best combination of:
A. Something interesting
B. Something that wouldn't require me going out of my way, and
C. A place I could go without any chance of getting lost.
I came up with Dell Rhea's Chicken Basket.
Great place. I definitely dug the whole "frozen in time" vibe. I got the fried chicken dinner, so I got to start with the soup and salad bar. Ah, iceberg lettuce, celery sticks, bacon bits and a mysterious "house dressing".
Obviously the fried chicken was the star of the show. I certainly don't know as much about fried chicken as a lot of others here, but this was definitely some of the best fried chicken I've ever had. Crispy, tasty exterior and impossibly juicy meat. If I wind up having to go back to Peoria, I would definitely make Dell Rhea's a stop again.