I'd say social life and then whatever you feel like at the time. College, I think, is more about getting used to interacting with people and figuring out where you fit that big old melting pot of society. Besides, as an undergrad you can pretty good grades with a minimum of effort. So get out there and socialize!
PS Drinking and crazy parties are not all that there is to the college social life. I alternated between beer pong, magic the gathering, and lan parties. It's amazing how many different kinds of people you'll meet, and how suprisingly well they'll all be able to get along.