The picture on my Sony TV seems to be too big for the actual screen. If you imagine the picture to be slightly zoomed in so it cuts the top, bottom & sides off the picture then that is what is looks like.
I've messed around with the all the settings but i can't seem to sort it.
As VHG mentions, there should be a button on your remote handset to enable you to toggle through the different options. On my (LG) tv it's called *Ratio*