What else do you want to know?
Most Hertz agents speak enough English for it not to be hard to collect the car. Of course all road signs are only in Italian, and Cordelli's warning about the areas in town centres where you are not allowed (or only allowed at certain times) is a good one - fines are issued and you will have to pay them if you break the rules.
Otherwise, it really is no different from anywhere else in the world.
Where are you collecting the car from?