Ubuntu to Kubuntu

[Winton Roseland]

I installed Ubuntu 2 days ago overwriting my Debian Stable install. I 
want to switch to KDE so I followed the instructions to use synaptic.  I 
get the KDE login but then I switch back to gnome.  The 
default-display-manager references kdm.  My gnome logout screen has 
changed to just allow a logout and then I must do a shutdown.  There are 
some kde accessories in my Accessories menu.  Any ideas on what is wrong?

Thanks,
Winton