I recently started using Hyper-V after being used to VMware. I want my virtual machine windows maximized, but not full screen since I need to quickly move between the host and virtual machines. In VMware the maximize button will do what it is intended for – maximizing the window – but Hyper-V will instead enter fullscreen mode when you maximize the window. Very annoying. It took me quite a while until I found a way around this:
Use the mouse to drag the window to the top of the screen. It will “snap” into place maximizing the window!
Note: This works only in “enhanced sessions”