You could try:
1) use tab key and space bar to navigate through the settings dialog
2) Install gnome-session-flashback via software center
<a href="apt://gnome-session-flashback">GNOME session flashback</a>
after installing logout, and before logging in click on ubuntu icon and choose GNOME session flashback metacity
You could try:
1) use tab key and space bar to navigate through the settings dialog
2) Install gnome-session- flashback via software center
<a href="apt://gnome- session- flashback">GNOME session flashback</a>
after installing logout, and before logging in click on ubuntu icon and choose GNOME session flashback metacity