I want to install KDE on Ubuntu 9.04. I would like to be able to keep my current stuff (settings, files, oh and GNOME). I would also like to choose which one to load before/right after I login. Can this be done and if so how?
At a terminal run
sudo apt-get install kubuntu-desktop
to install the KDE desktop environment. You will be prompted to choose your default desktop choice, but will also have the option to select at login which environment to use.
If you decide later you don't want it just run
sudo apt-get remove kubuntu-desktop
from the terminal to remove it
Here's the step-by-step instructions:
You might want to give it a quick look over to read about some of the issues you might not have thought about... mainly that you'll have cluttered application menus full of KDE applications and Gnome applications. :-)
Hope this helps.