Q:

Ubuntu 12.04 Update not working

I have installed ubuntu 12.04 through update manager, I had 11.04 as the previous version and everything goes fine from downloading the packages to restarting the system.        
After restarting I found that there is no graphics related items in the installation and I cant able to move my trackpad in laptop.  It shows a black screen with the desktop items but cant able to edit any items. 
There is no menu items available in the desktop.  Can any one help me in this. 

A:

As mentioned in my comment, I had exactly the same problem.  I solved it by doing the following:

Boot into recovery mode. 
Login and hit CTRL + ALT + 1
Type sudo apt-get -f install
Wait
Type sudo shutdown -r now
Wait
Profit!