Wow, there are a lot of really great questions being asked here. This particular Pope piece is a wonderfully comedic bit of poetry, and once students begin to understand what is being presented to them, there are several parts that they generally find quite funny. It's really up to individual reader opinion to decide which part he/she believes is the most humorous. I generally find two specific parts funny enough to be considered my favorites.
The first is in Canto 1. Specifically, it is when Belinda is getting ready to go out. I always chuckle at how her beauty regiment is likened to a form of worship. As a male, I can't imagine that ever going through somebody's head; however, I hesitate to call it the most humorous part. I hesitate because I think that concept of self-objectification is alive and well in modern day society. It's possible to think of Pope being hard on women in this sequence, but I think he's using it as a form of social commentary. He's not encouraging Belinda's behavior and attitude. Rather he's pointing out the ridiculous nature of it. How sad that a woman gets dressed as a form of worship and battle preparation.
I've always found the card game in Canto 3 fairly funny. The game is talked about and described like it is some huge, epic battle.
Let Spades be Trumps, she said, and Trumps they were.
Now move to War her Sable Matadores,
In Show like Leaders of the swarthy Moors.
It's a card game for crying out loud. Pope intends for this part to be completely over the top, and that is what makes it so funny.
As for whether or not this poem would make a good movie, that is again up to individual reader opinion. It could work. The physical actions that occur wouldn't be that difficult to get actors to do, and the mystical Nymphs could easily be done with today's special effects. The story itself would work as a film; however, I don't think the underlying themes and messages would translate well to film. Hollywood has absolutely done satire in film before; however, it is up for argument how successful those films are. If a movie that "works" is defined by box office numbers, then most film satires perform poorly. On the other hand, many of Hollywood's top ranking satires do very well with academy awards and nominations. American Beauty comes to mind. It won 5 Oscars and was nominated for 3 more. It has been reviewed quite well, but it only earned 130 million dollars at the box office. That ranks it as number 448 on the all time earning list. I think this Pope poem would fall into that category. It could be a great film that audiences don't like watching.