The best oils/fats are tallow and lard from pasture raised livestock (meaning they weren't fed grains, which contain lots of chemical sprays). Secondary to that, is butter (from similarly raised livestock), extra virgin olive oil, extra virgin avacado oil (make sure its real, as most avocado oil is fake), and extra virgin coconut oil. There is still some debate about coconut oil, though.

Get organic if you can. Never use seed oils. Never use anything other than extra virgin for oils, which uses mechanical means to extract the oil. Every other type of oil uses chemicals to extract the oil, and often other chemical additives to mask the rancdlid taste.