I'm just getting into biking, hoping to make it a primary part of my commute. I picked up a nice bike of craigslist that the useful folks here helped me identify as a 2007 Cannondale Road Warrior 500. It was in brand new condition, and clearly has just been sitting in someone's closet for the last 5-6 years.

As a general newbie to bike care/maintenance, what sort of work should I do on a bike that's been sitting around so long before taking it out for a ride?