Why does my laptop display black borders on my TV?

Q I have a slightly ageing Samsung NC10 network that I connect to my TV to watch programmes on BBC iPlayer, as well as clips from YouTube. My laptop has a resolution of 1,024x600 pixels, while my television, an LG 22LS4D, has a resolution of 1,680x1,050 and an aspect ratio of 16:10.

I have upgraded the NC10 so it is now running Windows 7 rather than Windows XP and I have the TV displaying a clone of the Windows Desktop. However, when I view videos in full-screen mode, I find that the full area of the TV screen is not used and I am left with black borders and a small picture. What can I do to fix this?
Bill Sully

A This problem occurs because the TV you are using as a second display not only has a higher resolution than your laptop screen, but also a different aspect ratio. The best option here is to switch the monitor so that it is no longer a mirror of the contents of the Windows Desktop and is instead an extension of the Desktop.

To do this, right-click on an empty area of the Desktop and select the Screen Resolution option. From the Multiple displays dropdown menu select Extend these displays and click the Apply button. Click the monitor labelled ‘2’ in the image and select ‘1680x1050 (recommended)’ from the Resolution dropdown menu. You can now run videos in full-screen mode on your TV without worrying about borders.