Hey Cry,
Well I take it you have a wireless router.
We need to know what brand of router you have so we can guide you in creating a security key.
If you have a linksys router, use this instructional video to create the security key:
http://www.metacafe.com/watch/321434..._from_hackers/
We can help you further if you like, but remember that you can find guides online. Just type something like "how to create a security key for (what brand of router you own.) And follow the instructions. It is very simple and shouldnt take long. If you have more than 1 computer using the wireless connection, like a laptop in the bedroom, you will also have to enter the security key or network key into your wireless network to gain internet access for that computer.