Photoshop CS2 is stretching my images on my new widescreen monitor?

I have just purchased a new pc and am running photoshop cs2. I have upgraded to a widescreen monitor and have noticed that photoshop stretches the image so it looks far from correct and almost unworkable. I have subsequently found out that in photoshop if you go to Image/Pixel Aspect Ratio and change to D1.DV/NTSC 0:9 then this improves the look. Is there a way of making this default now I have a new screen...or am i doing something totally wrong.....My monitor is set to 1280x1024, but I am not sure if this is right, any clues hw to check?