Can you play rock band 2 with the controller on xbox 360

okay so i just got the game from gamefly today. i went upstairs put it in and started up a song, but it only gives you the option to use the mic, not a controller. i cant figure out if there is a way to toggle to a guitar instead of the mic cause i only have a standard xbox360 controller. I'm gonna be extremely mad if it doesn't work because im a beast at controller hero.