Can anybody recomment a GOOD movie about Chile set during those years

The Chilean movie "Machuca" is very good.

Unfortunately, people are extremely political about this subject still, and I don't know why. Regardless of whether you're "conservative" or "liberal", the torture, murder, and "disappearance" of thousands of defenseless people is tragic, whether it's done by a "right winger" like Pinochet or a "left winger" like Joseph Stalin.