Classic scrollbars in Ubuntu 12.04
Tested on Ubuntu Linux 12.04 Precise Pangolin. (2012-06-06)
To switch back to the classic scrollbars in Ubuntu, execute the following command in your terminal:
option A
sudo apt-get remove liboverlay-scrollbar*
option B
gsettings set org.gnome.desktop.interface ubuntu-overlay-scrollbars false
related links
Michael Koflers Blog: Meine Unity-Konfiguration
Liberain Geek: Disable Ubuntu Overlay Scrollbars in Ubuntu 12.04 (Precise Pangolin)