Thank you guys so much for the information

Haven't checked into it yet, but I'm don't exactly like the idea of enabling DMZ. I'm on a LAN with my computer, my sisters and mothers and my fathers, which have bank accounts and such so enabling all ports... errr.. not good

If I just enable it to this computer I can just run an image of the harddrive and if something should happen (you never know with hackers and such), I can just remake it (my computer is filled with a bunch of crap anyways). Just have to make sure that the others computers on a LAN network is unreachable in that scenario.
The alternative - forwarding ports - sounds a bit more like the thing I should use, but I'm still a bit confused about what I am to do (I consider myself to know a little about computers, but this thing about routers is like a person came up to me and tried to start a conversation with me in chinese). Speak to me like I'm an idiot, I won't take offense

Also giving me a hint on what ports to actually forward to be able to make that god damn server to work would be neat :P
And yeah, sorry about confusing you, really meant the D-Link DI-604 router (am running on 1024kbs)