Hi Andre,

Kindly find my response for your inquiries below:

1- I would like not to have the menu (so the unregistered can not see the profiles of the registered)

You can hide the toolbar to guest user by head to the setting shown: http://take.ms/ijVjQ

2- I would like to remove the background. I would like that the home of easysocial for non-registered was just the possibility to register. how can I do?

I'm not so sure what you mean remove the background here. Or do you mean stream feed below login section?
We actually got setting for guest user cannot access EasySocial's system unless he register into the site, where you can activate the lockdown mode as shown: http://take.ms/M2KtQ