I eat everything but it's easily Asian first, followed by Europe then the Americas.
Asian food is just so diverse. The flavourful currys of India and Nepal, the amazingly delicate and fresh Japanese fish, the meats of the mid-East, the mass variety of Chinese recipes, the spicy recipes of Thailand, the fresh water fish dishes of Cambodia etc.
Europe has great food but outside the mediterranian countries the food can be somewhat bland, especially in comparison to the sheer variety of flavoursome dishes available from Asia. Having said that, I still love my Pasties, German sausages, Hungarian meat-bread, Swiss Chocolate etc. But if this was a contest on alcohol, Europe wins hands down.
As for the Americas, Mexican food is brilliant. Burritos are easily my fave post-beer food now and I love mole sauce. In the US however, I think most foods are imported from Europe (e.g. Pizza = Italian) but some recipes have come out that are unique and very tasty.
I haven't experienced enough of African and Australian food to really say how good it is but I know North African food is delicious, and I like some of the frsh water fish dishes from coastal regions of Africa. All I know out of Australia is they do great Barbeques!