Top of the list is pepperoni.
Top two is pepperoni and bacon together (a local joint runs a special on two topping pizzas sometimes and this is my go-to).
Like the Captain, I'm a "the more meat on my pizza the better" type of guy, so I put sausage as my third choice. However, Hawaiian is pretty good and onions and bell peppers are also great on a pie. The pineapple has to be flavorful, though, and not bland.
I haven't actually tried pepperoni and pineapple before. I'll have to remedy that....
No mushrooms, olives, chunk tomatoes, anchovies, etc. OK with light diced jalapenos, but the flavor can overpower. I like semi-spicy food, but some folks take it overboard.
Straight cheese is one my son goes for sometimes, but it is way too bland/boring for my taste.