To change your resolution: right-click on the desktop, choose Display settings, click on the monitor (if you have more than one), then use the dropdown to choose a Display resolution (see the related item below for the supported sizes).  Be sure to set the Scale to 100%.
 
If you choose a resolution that exactly matches one of the 3 supported GOLD screen sizes, the window should just fit with the taskbar at normal size along the bottom edge of the screen.  If you have two monitors, it might help to move the taskbar to the other monitor, even.  (Right-click on the task bar and use the Taskbar location and Multiple displays controls.) 

If the optimal size for your particular monitor doesn't exactly match of the 3 supported resolutions, be sure to select a higher (larger) setting than the minimum supported resolution.