Instructions
Turn on your television and Xbox, and log on to Xbox live. Scroll up with the left analog stick of your controller, and press the "A" button -- the round green button -- when you get to "Video Marketplace." Scroll to the right, and press "A" at "Netflix."
Scroll up or down on the screen, until "Instant Queue" is highlighted. Scroll right to find the title you want to remove, and press the "A" button on your controller.
Scroll down until "Remove from Queue" is highlighted, and press the "A" button. The title will be removed, and you will be redirected to your instant queue.