Linux N00b here, please be gentle

My question is: Am I doing it right?

I had 4 days to learn about and set up a linux server and as far as as I can tell it is set up correctly.

I get the apache success page when I access the local IP locally. When I type the dynDNS URL into Windows 7 RDP it lets me successfully login to the server with gnome classic GUI. When I type the same dynDNS URL into a web browser I get the router's configuration page.

Here's what I did:

I set up a dynDNS account and set my E1000 router to use the DNS.

I installed SSH, X11RDP on the linux server.

I then port forwarded the RDP, FTP, and SSH ports to the static IP of the linux box.

I also set up ddclient on the server, and set the dynDNS info.

Is that a mistake? To have the router set up to dynDNS AND the server is correct?

While I was testing the server, it seemed to work once. Then, I logged out, restarted the computer, it gave me an ICEAuthority error when I tried to remote access again. I followed a guide online and did CHOWN blah blah on the file and it does seem to work now after a restart.

Now I'm nervous that once I log out of this session I will lose access to the box again. Assuming the system is still powered on, how do I manage this server so I don't lose access? I have a linux system at home as well that I could use for accessing the remote server, but I was planning on using RDP just to check my cameras on Zoneminder.

Any thoughts? Any blaring mistakes, or suggestions?

Just an update. A friend tried to access a guest account on the server via RDP and was given the ICEauthority error

"Could not update ICEauthority file /home/user/.ICEauthority"

I am still logged in under the main user, so I haven't yet lost access to the system. Once I log out, if it does give the .ICEauthority error, will I have lost access to the machine? Can I do anything now to ensure that it won't?

I won't be physically present to do anything to the machine...