How to fix Xubuntu LightDM Theme after installing unity.

After successfully installing Xubuntu 12.04.1 on my laptop, I decided to install Unity. That went OK but then I realized there was no themes. So then I installed the themes and artwork, and got a really bad surprise. My lightDM greeter was still Xubuntu like I wanted but the buttons where you choose the user are really tall and I have a purple computer as the icon above my computer name. How do I get back to the original Xubuntu configuration or edit the CSS while keeping Unity? I know where all of the files are but don't know which file to edit or which CSS property to modify.

Packages Installed:

unity unity-services unity-mail

Then I Installed:

ubuntu-artwork light-themes ubuntu-wallpapers-oneric ubuntu-wallpapers-precise

Solution 1:

Check the content of /etc/lightdm/lightdm.conf. To get back to the Xubuntu config, make sure the greeter-session parameter is set to 'lightdm-gtk-greeter', ...like this:

greeter-session=lightdm-gtk-greeter

To edit the file, run gksu leafpad /etc/lightdm/lightdm.conf.