login and password window

someone knows how to generate that small window that apears when you go into a member area of a secure place that ask you for a login and password, like window does.

I did something similar but to do what your thinking of I had to set up server side access rights to a particular folder which contained the files which you can only see when logged in.

However I dont how your code doing and it might be useful to know this:

opening a window in javascript is simple through

var passWin = window.open("login.html", "windowName", "windowProps")

In windows, you need to setup the permissions to prompt for a password. In UNIX, you use the htaccess/htpasswd files. It isn't part of javascript.