I love movies like this for the insight they provide into the customs of a lost era. Watch the clothing - everybody is so dressed up! - women in dresses, gloves, and hats, men in hats and suits. Notice that when O'Hara enters a room filled with Macy's executives, even though they are the bosses and she is lower management, they all stand up instantly.
The social satire, most on display in the courtroom scenes, also is very 1940s. Apparently audiences of that era took a kind of genial corruption in the judicial system in stride. Business leaders, like "Mr. Macy" were expected to be sharp and profit-oriented, but also decent people like the rest of us. It's a much more nuanced view than the "businessman as criminal villain" so common in today's movies.
The character played by Maureen O'Hara probably needs explanation for modern viewers. Late 1940s audiences knew that the social and economic situation of a divorced working woman with a child was much more precarious than it is now. Divorce was still somewhat shocking - this is brought out neatly in the movie when her would-be lover does a double take when he learns from her daughter about the divorce - he probably had assumed she was a war widow. Divorced moms were still rare in the middle classes. Society universally agreed that women should stay home to raise their children. Economically, women in management positions were still very rare, couldn't expect promotion, and were last hired, first fired. I think O'Hara's performance brings out these qualities in a way that the audience of the 1940s would have understood easily. The character's stiffness, fear of losing control, and anxiety about her job make a great deal of sense. It would have been nice to see a few scenes showing her loosening up, perhaps at dinner with her boyfriend; no doubt those got left on the cutting room floor.
I really like the scene where Santa talks to the little Dutch orphan. First, this scene also must have resonated with the audience; in 1947 the western European countries had only started to recover from World War II, and probably many Americans were familiar with the idea of adopting a war orphan, just as many sent CARE packages. Second, by making Santa fluent in Dutch, the writer cleverly left the viewer thinking that hey, he might really be Santa Claus (isn't Santa Claus fluent in all languages)?
Some reviewers don't like the acting and think that modern actors are "better". I think the older actors aren't better or worse, just different. The audiences of the 1940s expected a certain style of acting, and the directors and actors gave that to them. Then as now, Hollywood paid top dollar and got very talented people, but like all of us they were shaped by their own time and place, more particularly the requirement to make movies that audiences would like. Move Maureen O'Hara to 2004, or Tom Cruise to 1947, and you'd see them acting in the style of that decade.