[Bruno]

Handy-dandy thing to know: you can easily rescue off-monitor windows using some VERY OLD but still perfectly functional keyboard shortcuts.

Press Alt-Space effectively drops down the system menu for whatever window has focus, even if it's hovering off screen. Because windows has SOME sanity checking built in, the system menu will be on screen even if the window itself isn't.
System menu is the icon at the top LEFT, if you're curious.
You can usually then use your mouse to click on "Move", and the window will snap to your cursor and you can put it somewhere sensible. Click your mouse to release.

If the mouse isn't working, there's a backup, also with keyboard commands!

Press the down arrow on your keyboard until "Move" is highlighted. Press "Enter" to accept "Move"
Tap either the left or the right arrow, either one will force the window on screen.
Press "Enter" to accept the new onscreen position, drag around with mouse to your preference.

This has been kicking around since Windows 3.1 when many people didn't have mice :)