Widescreen monitors typically use either an aspect ratio of 16X10 or 16X9. Not too long ago, 16X10 was common, but 16X9 has become more popular because it matches the same aspect ratio as the hi-def 720/1080 standard.
Typically, a hi-def monitor will use 1920X1200 if it is 16X10, and it will use 1920X1080 if it is 16X9.
I checked the specifications for your ST2410 monitor and it is indeed a 16X9 aspect ratio monitor, using a resolution of 1920X1080, so that's what you want to set your desktop resolution and your aces high resolutions at.
You also need to go through your video card settings... select "Enable GPU Scaling" and select "Maintain Aspect Ratio". This should eliminate the bars at the top and bottom of the screen, and the black bars on the side should only appear when you use a more narrow resolution (a non-widescreen resolution for example like 1280X1024).
The "Maintain Aspect Ratio" should have the same affect as the "Scale-to-fit" example in the following illustration:
