Just another thought, along the "anything is worth a try" theory, assuming you run your games from shortcut icons on your desktop, how about right clicking the icon, then selecting the 'Shortcut' tab, and change the 'Run' option to 'Maximised'? Below is a screenshot of what I mean. That particular example is set to 'Normal Window', but you can change them, so that whenever you launch the shortcut, the window opens Maximised.