My wife placed some files on the keyboard, and suddenly the display in the monitor went upside down. After reboot, it remains the same. She again placed some files on the keyboard, and this time the display changed to the side, i.e. 90 degrees from the normal display. I tried to press every single key on the keyboard, but cannot put the display in the monitor right.

Have you got nVidia graphics card? If so there is a utility that is in your system tray. Don't use nVidia graphics at work, but it may be the answer to your problem.

If it is an Intel board with onboard video, these hotkeys may work:

<Ctrl> + <Alt> + <Right Arrow>
<Ctrl> + <Alt> + <Down Arrow>
<Ctrl> + <Alt> + <Left Arrow>
<Ctrl> + <Alt> + <Up Arrow>

My wife placed some files on the keyboard, and suddenly the display in the monitor went upside down. After reboot, it remains the same. She again placed some files on the keyboard, and this time the display changed to the side, i.e. 90 degrees from the normal display. I tried to press every single key on the keyboard, but cannot put the display in the monitor right.
Someone pressed a key on monitor now picture is upside down. How do I fix this problem?

What graphics \dapter are you using? GEForce 4.

To access settings:
Right click in the task bar select "Show the Desktop"
On the display but off the taks bar, right click "Properties"
Select the Settings Tab and Advanced
Select the GeForce4 tab
On the left hand side select NVRotate depending on what is selected, select either Landscape or Inverted Landscape

Try, and let us know