Tiny problem with screen resolution (Not what you're thinking)

I've got a small problem with my screen resolution on my Sony VAIO.

It was bought in 2008 when the whole wide screen thing was starting to get big, so it's kind of like a in-between thing (not 16:9, not 4:3).

Because of that, all the resolutions I'm allowed to pick for the screen either leave a big black bar on the right or repeats the grey mac os x bar on the bottom (In other words, the resolution is about half an inch smaller than it should be on the height)

My question is if there's a way to make the resolution a bit bigger on height so that the second bar disappears (currently it's working as a mirror lol) or if I can customize the way it shows up so that it can only be a small black bar - it bothers me much less than a mirror grey thingy.

Thanks for helping in advance.