Like Chicago, it's called deep dish. xD Not square.
My favorite would have to be the aforementioned or Chicago. (I live in the Midwest if not already obvious)
My favorite topping is pepperoni by far. The staple of pizzas everywhere. After that it's dependent on how I'm feeling. Bacon is always second choice, but after that: ham, extra cheese, hamburger, chicken and others come into play.
My favorite pizza is a deep dish that's topped with extra pepperoni and bacon and has a cheese stuffed crust that's been brushed with garlic. <3
Of course I love nearly all pizza and have had a lot of different combinations. From Hawaiian to just crust and marinara sauce. Most of them are great, but a few just don't belong together.
Aside from Pepperoni and Bacon, I LOVE garlic butter. Although it'll give me a heart attack eventually I can't keep my hands off the stuff when I have the correct kind of pizza to pour/dip it on/in.
As for sides I'm happy with garlic bread or cheese sticks. Both add just the right amount of carbs to the already massive stack I intake with the pizza alone. As with the pizza itself I've had most of any kind of side you can think of with pizza. Chicken wings, salad, vegetables, fries, chips and so on.
To top off the meal a nice drink goes a long way. Sadly I don't drink alcohol, so I can't recommend a nice brew to complement the rustic flavor of a pizza. Really though almost anything will go with it. It's like the colors black and white. They match with anything.
Edit: I f**king love pizza. It's my favorite food.