Is there a quick way to set the size of the model space window.

I'm looking to size my model space window so that it is exactly 1280x720 pixels of viewable area for the sake of using plot to .png to create the right size images.

Is there a quick command or menu somewhere that shows the current viewable area of the model space window and allows for it to be changed?

I am using AutoCAD 2012.

Check out the LIMITS system variable. There's a good explanation in Express Tools and you also have the F1 button.