The developers at Canonical decided to move the position of the minimize, maximize, and close buttons in Ubuntu 10.04. For most people like myself this is an unwelcome change. We are used to clicking in the top right to minimize/close windows.
Fortunately changing this back requires running only one line of code:
Open up terminal, or the run application box (Alt-F2), paste the following command in, and run it:
gconftool-2 --set /apps/metacity/general/button_layout --type string menu:minimize,maximize,close
These changes should be instantaneous.
Moving Back to the Left Side:
If you ever want to change this back, all you have to do is run:
gconftool-2 --set /apps/metacity/general/button_layout --type string close,minimize,maximize:
If you are wondering why this has been changed, see this post:
http://www.tuxguides.com/ubuntu-why-the-buttons-were-moved-in-10-04/