does the ubuntu server come with a gnu?

No the standard Ubuntu server doesn't come with a GUI installed, you can however install any of the Desktop Environments from the Ubuntu repo's e.g GNOME, KDE, XFCE etc. However for a server build i usually use webmin or else the standalone Ubuntu server based system, Zentyal platform, http://www.zentyal.org/

Any more info you need please feel free to contact me.

Yeah I thought GUI was meant too, GNU is not the desktop. The default Ubuntu uses Gnome as the desktop, the default KUbuntu uses KDE and so on. If you need a desktop OS then install the desktop OS. You can install server based apps on the desktop OS with no adverse effects. The idea of the server OS is to maximize resources to the apps by NOT running a desktop but you will need to manage the settings and apps at command line and manually editting config files. If you are not comfortable with this then you can easily configure things in the desktop. You will however impact the system by using slightly more resources to run the X server, its drivers and all the things used in a desktop OS. It also reduces security as you are executing more services in the desktop OS.

If you install the server OS then install an X server like many users do then you have EXACTLY the same as if you'd installed the desktop OS except you have a lot more services running as you have the server stuff running as well as the desktop stuff.