Just to update; I took my iPhone to a high street Electronics 'Fix-it' place. They told me that the screen was good and that it was an internal problem which they could not cure. I then took it to Apple. After plugging the phone into a iPad for about 30 seconds they told me the problem was the screen which is part of the microphone-camera-select button system and all would be replace for £120 + VAT. 1 hour later all done.
Aaron.