I'd like to use my game controller as a joystick for my laptop when traveling. I can get all figured out (I think) except the throttle control. The right stick always centers which would result in half throttle all the time. Has anyone else done this and, if so, how did you handle the throttle control?

Use 2 of the buttons for throttle up/down. If you are using an XBox 360 controller with FSX, it already has a built in mapping for all the buttons and controls.