Have you run your own server (perhaps just on your home LAN), to get the general idea of how things work?
If not, I suggest you try this as an experiment. It'll give you a feel for what you can and cannot do under different circumstances. And you'll learn how to recover from "disasters".
Examples:
1] I got a new laptop last week. Pre-installed Win7 went straight out of the window. I made a new installation of ubuntu 10.04 (I am used to 8.04). Minor problems with the graphics which I (stupidly) messed up badly at my first (lazy - clicky-clicky GUI-do) attempt, so eventually I could not even login.
So I reinstalled and then enabled ssh on the new install (with clunky horrible mismatched graphics), before I messed with anything else. Then I tried different GUI configurations. But I now had a "backdoor": No login screen to the laptop? That's now easy to fix: just ssh in from another PC on my LAN so I get a terminal talking to the new laptop and fix the problem(s), reboot from my ssh login, and laptop restarts remotely (well, it's really 3 feet away, so I could watch it restart) with GUI working. All is happy
2] Sometimes I play with my (LAN) server too much, and break it.
So I boot it from a live CD (So the server is "turned off" in the sense that it is not running, but the live CD is), mount the server's filesystem, so I can access its quiescent files, and fix the configuration. Logout from the live CD, and reboot: It works again
Or, as above, I can ssh into it, fix the problem, reboot it, and I don't even have to walk upstairs.
I encourage you to experiment with your LAN before you try esoteric remote server administration.
Hope this helps.