I guess that's a no naki frown.

There is a flaw there, a typical start menu is 28 pixels high.
My screen resolution is 1024x768.

When I use $window(-1).h it returns 768
if I use $window(-2).h it returns 748
You say that that shows the height of mirc's window.

How could mirc be 748 if the taskbar is 28 itself and my screen height is 768?
768 - 748 = 20
Taskbar = 28

748 + 28 = 776

Taking a snapshot of the screen and using a good ole adobe program tells me that the true height of mirc window maximized is 740

Does that mean mirc is hiding 8 pixels height somewhere behind something?