As far my understanding, in the current context of Ubuntu 11.04 Lucid Lynx we have a greatest change in desktop. We had our beautiful gnome look but with the updates to 11.04 Lucid Lynx, we will not see the default gnome look but we will be seeing Unity. Unity was famous in net-book editions. As the unity are not completely stable, so you may have been facing problem. So, for your beautiful to get back, here you what you have to do.Just do the following things :
1) Log-off your computer.
2) Click on your username.
3) Then select “Gnome” at the bottom of your PC.
4) Then type your password and login.
5) And you get your beautiful gnome look back.
Now then you enjoy it.