Themes how i can make default

[mgamboa]

How i can make a default theme in the login screen and how i can hide the another themes i need only the user can see the theme for default and the another themes can hide it

[Superman]

Open ./config.php and find 'default_theme'.
Then delete all folders, except for yours theme, in ./themes/, or
just edit ./modules/Users/Login.php (there you'd see HTML-code of login-form) (hide there options for theme)