The computer in my sons room is hooked to the internet but I would like to hook up my computer in the kitchen to the internet also. What do I need to accomplish this? The computers are about 20 feet apart or so. Please make it simple terms as I am not a computer person.
Your best option would be a wireless network. You would need to buy a wireless router to connect to your broadband router (I assume you have broadband to your son's computer) and a wireless adapter for the kitchen. A USB adapter is best since you don't want to open the case of the kitchen computer. They should come with instructions. You can go to this site for an in depth overview of networking.
You could also do what he said, it's nice to have wireless, but make sure you put a password, If your son plays games or does stuff (Runs games server like I do) I suggest TrendNet As your router as portforwarding is a easy step.