I am wondering when hosts say they give you root access over ssh what does this mean?
Does it mean that you can log in using only command line?
Or can you use the gnome desktop (or whichever your preference) over vnc or some other remote access?
Also, whats the benefit of remote access, will a hosting provider let you install software with this?
I guess one other benefit is that you can create new users for the server?
In general, that just means that they give you full root access to your system. Most of the time, they provide this via a remote ssh terminal. By default 99% of server providers will just give you command-line access, but with that, you have the ability to install a graphical environment if you choose. You'll need to use remote X or VNC to display the GUI environment, though, as most providers won't let you get access directly to the console of your server, especially if it's a VPS.
With full root privileges, you can do whatever you want on the server. That is, as long as you stay within the AUP of your provider. This includes installing applications, copying data, adding users, setting firewall rules, and whatever else you want/need to do.
As an aside, though, if you're serious about learning how to administrate a linux server, I'd highly suggest not installing a graphical environment. Yes, there's a steeper learning curve to the command line, but once you learn it, it'll stick with you your whole life and you won't ever regret learning that skill.
This means you are the administrator on the server through SSH.
SSH stands for secure shell and you can compare that to what is known as the command line in the Windows world. You can be able to set up a gnome desktop if you want and use VNC to get to it. But this is usually not pre-installed since most admins don't need it on a server.
You are free to install any software you want. Unless your EULA mentions any particular service your not allowed to set up.
