How to make laptop stretch when connected to HDTV

[wuddhabatt]

I'm trying to connect my laptop (Toshiba Satellite C660D-1GR) to my HDTV (Toshiba LCD Colour TV) using a RGB cable. The laptop doesn't have an HDMI cable plug-in, so I'm confined to a RGB.
Anyway, I'm seeing the picture from the laptop fine on the television, but in 4:3 format. When I set my laptop to show on the monitor, the laptop display ALSO appears in 4:3. When I change the setting on the laptop back to 'PC Screen Only', the laptop display returns to normal widescreen. I'm trying to stream movies so, as you can imagine, a 4:3 display ruins the entire effect.

As the picture is usually widescreen and fine on my tv, I can only assume it is a laptop problem Is there some sort of setting I should be changing on my laptop? Or is this a consequence of being left in the dark ages using an RGB plug?

Any help would be greatly appreciated.

 

[americanaudiophile]

If you haven't done so set the external monitor out as a second display rather than a duplicate of the laptop screen. Then you should be able to set the output to match the Toshiba TV in the video display controls of the laptop.