There are a few good places in Downtown Middleton:
Hubbard Street diner - they serve a little of everything, but especially good for breakfast and pie
Roman Candle - good pizza & ice cream
Barrique's - coffee shop/cafe/wine bar.
Imperial Garden - not sure if this is officially Middleton or Madison, but it's very good Chinese-American food with a huge menu.
Will add more if I think of any...