Stage to screen . . . the various versions of _Show Boat_ would be worth taking
a look at.  The musical itself was a bit of a pathbreaker, both formally and
topically, for taking up the issue of race relations.  Hollywood's adaptations
of it are both really good movies and, more significantly, interesting in what
they do with the show's themes.  _Footlight Parade_ tackles some themes of
Depression era poverty, but I don't know if it was adapted from a broadway show
 
Maternal Melodramas . . . One horrendous recent example:  _The Hand That Rocks
The Cradle_, in which a mother's  "selfish" decisions to report a harassing
gynecologist and hire a nanny in order to continue her career are repayed
with violence and the near destruction of her family (This film actually
also has a highly disturbing racial angle, making it a really remarkable
compilation of some of our culture's pathologies!).  Also, a note on _Not
Without My Daughter_:  it was pointed out to me that the film is, in fact,
an almost precise remake of _The Man I Married_ (1939), one of Hollywood's
first significant anti-Nazi features (based on a famous magazine story
called "I Married A Nazi") in which a NY woman, married to a German-born
U.S. citizen, follows her husband back to Germany to deal with some
family business.  In Berlin, he becomes involved with Nazism and demands a
divorce and custody of the couple's young son.
 
Also, while on the subject of maternal melodramas, I can't resist putting in a
plug for an older one, _My Son John_ (1953), possibly the most infamous of
the anti-communist movies of the Cold War.  Overly loving mother + ineffectual
father = (gay) communist son.  Must be seen to be believed.
 
-- Ben Alpers