Der Bingle. Quite possibly one of the best singing voices of all time. Very possibly one of the most despicable men in Hollywood.
The story's simple, idealist-Americana: Young priest comes to a financially troubled parish to try to turn it around while not offending the older priest, who's built the place up from nothing (literally). In the meantime, the young priest befriends the local hoodlums, turning them into a prize-winning boys' choir, and dissuades a young woman from a life of prostitution (or "being up to no good.")
Naturally, it all works out in the end, and Father O'Malley goes on to work his magic at another parish (with Ingrid Bergman).
It's sweet, in the way uplifting movies of that time were meant to be. It has the requisite happy ending. Bing sings, which is always a pleasure. It's the height of cruel irony to see him interacting positively with children.
This wouldn't be on my list of favorites, but it's a standard, much like White Christmas.