The server edition of Ubuntu is great, but lacking in interface. It is
strictly command line. You can install a GUI but that kind of defeats the
minimalist approach to running a server, that is, having maximum avail. RAM
and disk space for the server software to run.

There is also a different kernel package installed with server.

You may want to familiarize yourself with the apt-get and apt-cache
commands, as well as aptitude. Then I'd get used to using nano as it will
be the most basic but easiest to use command line text editor.

What services are you planning on running?

Also you can run a server platform even from Desktop edition, nothing says
you can't, I did for years. However, the resources consumed by gnome or any
other GUI services installed will be locked up in those services instead of
the apps you are serving.

Also, if you plan to administer the server remotely, remember, never use
telnet, only ssh.