[for Ubuntu 12.04 LTS - 14.10]
Launch "Ubuntu Tweak."
Go to "Tweaks" tab and click on "Login Settings" entry.
To gain access to the settings, click the Unlock button at the top of the window.
Change each setting as below.
*Draw grid: That grid of dots the login screen displays over your background image. Press the button to switch off.
*Play login sound: You can switch it on or off. It's up to you.
*Gtk theme: Select "Moe-Pink(3/4/5/6)" theme.
*Switch the "Login Screen Logo" to "moebuntu Login Logo":
Save the logo image below with right click/"Save Image As..."
Click the screen logo image on the settings screen,
then choose the downloaded moebuntu logo.
*Change login screen background image. Choose your favorite one.
You can download your favorite image from: theAnimeGallery.com konachan.com
I recommend to use the image of the character(s) from the same series as the Desktop Wallpaper you have chosen for creating a unified image.
The sample here is from: theAnimeGallery.com
[for Ubuntu 15.04/16.04 LTS - 16.10]
1) Install "dconf-editor" & "gksudo" via "Ubuntu Software Center".
2) Open Terminal and run the commands below to launch the "dconf-editor".
(Do not include "$")
＄ xhost local:
＄ gksudo -u lightdm dconf-editor
*draw-grid: That grid of dots the login screen displays over your background image. Off the check box.
*logo: Enter the directory of the moebuntu logo of the screen left below.Enter the directory of the moebuntu logo of the screen lower left.
*theme-name: Enter the desktop theme name [Moe-Pink7] or [Moe-Pink8] for moe.
In Ubuntu, because the default setting for the login screen is to display the same Desktop Wallpaper,
you cannot see the Wallpaper you have set for the Login Screen unless you select a "guest sesson" from the user menu.
But it is possible to change displaying the Login Screen Wallpaper normally.
Open Terminal and run the commands below:
$ xhost +SI:localuser:lightdm
$ sudo -H -u lightdm gsettings set com.canonical.unity-greeter draw-user-backgrounds false
Then logout and see the result.