Question : Standards domain users to be allowed to RDP only to 1 standalone server that belongs to the same domain.

Is it possible to do this? I can grant permission to RDP to any user in the domain (Default Policy), but Can I allow to log on standard users only to 1 server on that domain, excluding Domain Administrators?

Answer : Standards domain users to be allowed to RDP only to 1 standalone server that belongs to the same domain.

You can add users/groups to the local Remote Desktop Users group on an individual server.  Easy way is to right-click My Computer->Properties->Remote tab->Select Remote Users.