I vote against skinny tires, especially for such a short commute. I ran Specialized Armadillos for my 10-mi commute, the time I lost with heavy tires was more than regained by no longer stopping to fix flats in the dark. I ran studs in the winter, not so much thorns and broken glass in snow. A mnt bike is the way to go for commuting, as long as it fits you well. Knobby side walls help lift the tire out of cracks and up curbs, that will save your butt eventually. I wouldn't put much into a college bike, I never rode my competition bike on campus, never left it outside unattended.