Sony Bravia TV - display problems

I have just moved into a flat with a Sony Bravia TV. I have hooked up my Dell Studio laptop to the TV via HDMI cable. However, the TV only displays as 'wide'. When the PC-TV settings are such that only the TV is displaying an image, the slight corners of the screen are cut off (e.g. the Start button, or the time display in the bottom left and right hand corners respectively).

Now, I've tried multiple times to change the setting via a button on the remote control, but though it registers that I'm pushing a button (the green display light on the TV flickers) NOTHING changes, and I'm left with what is essentially a cropped image.

Does anyone know another way of changing the settings on the Sony Bravia TV from 'wide' to something more standard?

Thanks