Problem installing additional controllers in Ubuntu 12.10

view story

http://askubuntu.com – I recently installed Ubuntu 12.10 and tried to make additional controllers work (instead of the developpers one) but when I reboot, after login, the Unity interface doesn´t appear, only the background image, no launch bar or else. I can access the terminal but I don't know the command line to reinstall open source controllers. What can I do? (I really don't want to format and reinstall Ubuntu). (HowTos)