Remove Guest Session From Ubuntu 14.04 Login Screen

Press Ctrl+Alt+T on keyboard to open the terminal. When it opens, run the command below to edit the config file:

Open /etc/lightdm/lightdm.conf file from your terminal using the following command:

sudo -H gedit /etc/lightdm/lightdm.conf

If the file exists, then just add the following line:

allow-guest=false

Save the file and exit the editor. Reboot your system,

How to disable automatic remote printer installation in Ubuntu

Press Ctrl + Alt + T to open the terminal 

1. Modify the cupsd.conf (/etc/cups/cupsd.conf) file through add the below mentioned 

contents.

Browsing Off
BrowseLocalProtocols none

2. and also add the below mentioned contents in cups-browsed.conf (/etc/cups/cups-browsed.conf) 
file.

BrowseProtocols none

after rebooting the desktop there is no automatically added remote printers visible except
those which we have added manually.