Here's just a little helper for you if you want to Remote Desktop through firewalls. There's a lot of info out there on this subject, but it's often quite hectic.
The only port the remote desktop protocol (RDP) needs is TCP port 3389 in and out. Many routers do port forwarding so if you have a machine on a LAN behind a firewall you can get to it via this protocol. For example, at home I have an Inventel Livebox from Orange. Using the config site for the router, I opened 3389 and pushed it through to my main server viathe LAN IP.
Now I can just connect to my internet IP or hostname using Remote Desktop and I get pushed straight on to my server. (here's another tip if you're using an Orange Livebox with a dynamic internet IP... the livebox supports auotmatic updating of Dynamic DNS such as dyndns, which I use... so all I need to do is connect my RDP client to danmatthews.dyndns.org and I don't care what the IP actually is!)