On the occasion of the 100th anniversary of cinema in 1995, the Vatican compiled this list of "great films." The 45 movies are divided into three categories: "Religion," "Values" and "Art."
Religion (1-15)
Values (16-30)
Art (31-45)
25th February, 2014: The original link seems to be gone now, but I've managed to find a website containing a snapshot of the lost page, including paragraph details of each film (now added in notes).