Not too sure it this post should be in customization...
Anyway, I'm having this strange bug with the background image in Windows 7.
When in Personalization>>Desktop Background, it's possible to change everything as normal but the image position.
It shows up all options, but no matter what you select, it always keep on the "extended" setting.
If you choose another option, it doesn't change the background (when the "desktop background" window is still open).
I've used the "windows easy transference" tool, and got my files from an old WinXP pro. Maybe some glitchy config messed it up?