Well this thread is just gonna be a tutorial for anyone who wants to play KOF\Fatal Fury\Street Fighter and other fighting games and also some brawlers.
This is GGPO : http://ggpo.net/download/
Now this is pretty much like Hamachi or Tunngle, just click on the link and you'll get the instructions of how to install it and how to set it up.
This thing has almost no Lag whatsoever.
Now if you're having problems about setting up your ports, please do ask for help (unless you're using an internet provider other than PTCL in which case I don't know squat about it -___- )
Well, that's all hope to see some of you guys on GGPO.