This is a hard choice. I love both of these movies. Ghostbusters is a really funny movie, with the quote that everyone knows "Who you gonna call?" However, Karate Kid has one of my favourite quotes, I don't know why it is one of mine, "Wax on, wax off."
Both had good storylines, but I preferred the Karate Kid's storyline, a true underdog story. Going from nearly nothing to winning the tournament against someone who's twice his size. It could happen inreal life. But Ghostbusters storyine is just stupid when you think about it. A group of guys who go around fighting and capturing ghosts, then they have to defeat the greatest ghost who is about to take over the world. Just really stupid IMO.
As Shocky said, nobody has grown up without trying the Crane kick. I'm only 14, even i've tried to do it several times. Its an awesome ending to a great movie, he uses that famous kick to end it. And the characters were played very well, whether it be the way you are made to hate the cobras, or how you love Mr. Miyagi and his different methods, each character is played very well. Ghostbusters also had some awesome acting, but it was more just being stupid for the most part of it, while The Karate Kid had more emotional and demanding acting.
I'm going to have to say the Karate Kid clinches it here, but this is going to be close.