Hello Linux Geeksters. As you may know, Ubuntu 14.04 Trusty Tahr has been released a while ago, in all the traditional flavors.
In this article I will show you how to install remove the white dots and disable the Guest Login option, both via the LightDM Greeter.
First, remove the white dots from the LightDM Greeter:
$ sudo xhost +SI:localuser:lightdm
$ sudo su lightdm -s /bin/bash
$ gsettings set com.canonical.unity-greeter draw-grid false
Now, disable the Guest Login option from the LightDM Greeter:
$ sudo sh -c 'echo "allow-guest=false" >> /usr/share/lightdm/lightdm.conf.d/50-ubuntu.conf'
$ sudo service lightdm restart
This is it. Now, your LightDM Greeter should look like this: