Whoa, wait. Back up.
Run how you're running XP by me again, complete with all whatever virtualization software you're running it in, or however you're emulating it. Most of us Windows lemmings assume you're running it as your main OS unless you say otherwise, because that's how 90% of the world does it.
And you shouldn't need to open any ports, unless you have a router between you and the rest of the internet. Which I do, by the way, but no port opening was needed.