I just re read your post and now I am wondering what did you do? did you install another copy of Ubuntu but with KDE along side the Ubuntu with
unity? or you just installed another desktop manager on the installation you already had?
You know Kubuntu, Xubuntu, Lubuntu are all the same distro just using different desktop manager which you can install them all on the same Ubuntu 11.10 you already had
You can do that by typing
sudo apt-get install kubuntu-desktop
sudo apt-get install xubuntu-desktop
sudo apt-get install lubuntu-desktop
Each desktop manager comes with different applications so if you want to run them all you will have a bunch of applications that do the same task. E.g. Music player in Gnome is Rhytmbox, music player in kde is Amarok, Video player in Gnome is Totem, video player in KDE is Dragon Player, or Kaffeine.
Good luck to you!