Should I use handbrake when stationary on an inclined road?

You should definitely use your handbrake when waiting for traffic to move on a hill or inclined road. This is what it's there for - to prevent the car from moving when you need to be stationary. It will make it easier for you to move off as well because you will get to balance the vehicle better when the handbrake is on and this means your car will not roll back when it's time to go forward. Many drivers have the bad habit of using their brake pedal instead of their parking brake when they have stopped at traffic lights. It is important that you do not follow them and that you secure your car by raising your handbrake when you are stationary.

Not only is it better driving to apply your hand brake at lights etc, it is also more considerate. You are not dazzling the person behind you with your brake lights.