New Book: Chapter 1- Sight and Sound

I personally feel that the main point of having sound effects in movies is to help enhance the mood, the setting, and the characters to make the movie seem more and more like a reality for the viewers.
EXAMPLES:
-Scary movies, to give viewers the feeling of being scared or afraid, creepy or dark music is played.
-Thrillers/Horror movies, suspenseful music is played to keep viewers on the edge of their seats.
-Cartoons and kids shows, sometimes small children might not be able to understand a scene or part and that is when the sound effects come into play. Sad music makes them feel for the character and happy music suggests that the character is being playful.
-Advertisements use different types of music to play the feelings of every-day Americans watching TV. They play sad music when they want you to feel bad for puppies, depraved kids in poor countries, and global warming melting icebergs and stranding polar bears.
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In the absence of music, it is harder for directors and actors to fully convey the mood to the audience.
EXAMPLES:
-Disney Movies. The impact of sound effects and soundtracks can be found in Disney movies. If you we're to watch one without turning on the sound (or at least without the music, in other words, just the voices), then you probably wouldn't feel as sad as you do when a character who is loved by all is hurt or killed (death doesn't occur TOO often in Disney films...but then again, there are a few exceptions...that I can't seem to bring to mind right now...but still).

-Other Movies. Even if it is not a Disney film, if you were to watch a movie (hearing only the voices), it would still be an entirely different experience. A man would be clutching the (prone and dead) body of a woman who he loved so dearly that he was willing to risk his whole life to protect her son even though she went off an married his childhood bully and arch nemesis and you might be sitting there, indifferent to it all thinking "...ok. Soooo...she died...that's too bad...*pausing the movie at the credits*...hm, I'm hungry...I wonder what's new in the refrigerator? *goes off to make a sandwich*"...well, maybe not exactly like that, but you probably don't feel as much empathy for the man as you would with music. With music you would probably still be sitting there in fetal position with your knees to your chest and tears streaming down your face while the credits continued rolling down the screen. then you would probably go update your status telling everyone how you were so touched by this movie you just watched. (...Alright...so maybe Harry Potter and the Deathly Hallows Part 2 isn't exactly an exemplary example of a drama, but still...).