Sorry, but your screenshot needs to be loggin to see it.
Anyway, if I understand your request, you want to change te words on the top left corner...
Simple, go to the administration panel and Configuration settings
There, on the first 3 lines, you will find what you need.
Then, you can change the url http://www.chamilo.org
If you only want to come back to the home page, delete this url and after that, when you click on that, it will come back to the home page of your site.