In the latest version of Ubuntu, the development community decided that they needed to look more like a Mac, so they randomly decided to move the window controls (to close, maximize, minimize etc.) a window, to the left (incorrect) side of the window rather than the right (correct) side of the window.
In order to fix this “feature” here’s what you do.
Run gconf-editor (enter that phrase into a terminal). Find apps, then metacity, then general, then within that find “button_layout”. Double click on that.
It will say “close,minimize,maximize:menu”
Change that to “menu:minimize,maximize,close” and click OK. Instantly, you will be fixed.