WinDVD platinum 7 widescreen problem ???

I have a 21 inch Gateway Widescreen LCD (1680x1050 res) and I cannot at all get WinDVD to utilize the FULL SCREEN when playing my DVD's..... and I will not use any other DVD players cuz so far WinDVD is the only one I've seen that uses Trimension DMM system, (to those of you who dont know what that is, les just say it kicks ass see for yourself)
ok for example I pop in my DVD I play it, I go to video center to enable everything that needs enabling, the first thing I notice is that SMART STRETCH is completely disabled, I cannot click it on, I cannot choose the 16:10 resolution which Im sure would remedy my situation, so I guess therein lies my problem.... does anyone know how I can fix this ??
because when I play the movies fullscreen they stretch fully in a horizontal manner, but vertically it only uses about 1400 pixels (out of a possible 1680) which leaves one huge fat black line on top of the image and another even fatter black line on the bottom ......
help anyone ??