It depends what kind of food you want to eat "gratiné" nt.January 19 2003 at 9:03 PM
Response to What sort of cheeses must one use?(nt)
you should normally use a full fat cheese such as Gruyere as long as you grind it. The cheese has to develop a strong own smell. Soft cheeses are not possible except for pizza.
But for special dishes such as Gratin Dauphinois (with potatoes) or cauliflower, you should use cheese and Béchamel.
On a Pizza I recommend Mozzarella and for pasta Parmesan cheese.