VPN Setup difficulties

Hi All! New here, so please be gentle :)

I'm trying to set up some home network VPN in Windows 7. I have searched google and even in here, but there is not to be found any real information on it.
I know, I know, the whole basic stuff of making a new incomming connection and the basic outgoing connection is easy enough, but I can't connect. I mainly get the Error 800, but have had one or two others (can't remeber what they were, sorry). I have found some information regarding the whole problem of being behind a router, and the guides I have found (which was REALLY old!) tells of port forwarding, mainly port 1723? (and should forward to what port?). This is a thing that I'm very green at.
My internet vendor has a small guide as to do this on their router, but it does not help.

So, here's the setup:

"Server" (192.168.x.x (static)) -- Router (188.181.x.x) -- INTERNET -- Client (192.168.x.x (dynamic))

As I said, the server is ready for incomming and the initial outgoing can be made, but will not connect. So... What's next?

Best regards
nkrogb

Sorry, wrong section :)

Here are a couple guides for setting up VPN on DD-WRT routers (but you can get the concepts of what needs to be done to get the connections through the router to your machine):

How to Setup a VPN Server Using a DD-WRT Router - How-To Geek
Remote Access your Home Computer – Setup a VPN with DD-WRT

Hi, thanks. I will give this a try, but, since I'm stuck at my parants house for until the 15. February, I do not think that I should go tinkering with their router. My father gets so easily pissed over small stuff. (like, turning on my mothers computer...)

Well, that's the main crux of the issue. You have to open the proper ports in the router for the VPN solution to work (assuming your router is implementing the VPN service). If your PC is implementing the VPN service, then you'll also have to forward the traffic to it.