This is really quite funny: it is now twice that slightly panicked family members have called me to ask how to rotate the screen in Windows XP back to normal after toddlers of about six to eight months of age have managed to rotate it to 90 degrees or upside down by just banging on the keyboards of their computers, as small children tend to do.
To do this, it seems that you need to have a display driver that supports rotation and installs the keyboard shortcuts for it:
- ctrl-alt-up/down/left/right arrow
It seems that children tend to hit the left or right arrow, leaving the screen rotated. This rotation survives reboots it seems,
To fix it, just press ctrl-alt-up arrow and the screen should be right fine.
I have not been able to duplicate this on any of my own machines, as that shortcut does not seem to be active on them.