I believe capitalism would be the way to go.
Seeing as how if everyone put their best interest in front of others, then everything would go a lot better.
Socialism is a tough one, I believe with socialism, people will find it unfair. Everyone would be paid the same for different jobs, there'd be no point in pursuing a college degree in a certain field if you're not going to get a bigger reward.
I mean, think about it, who would want to spend a ton of years in college to be a doctor to be paid the same as someone working at a fast food restaurant?