Xbox via laptop - Bridging connections not working?

Hey all. I am trying to connect my Xbox via a Windows XP laptop that I hardly use.

I've read the instructions online at several places, and they all boil down to this:

Make a wireless internet connection. (Which I can do)

Make a LAN connection with the Xbox. (Which I can do)

Create a bridge between these to connections... which I CAN do, but once I do the internet no longer works. It either disconnects or SHOWS it as being connected but I cannot access the internet on either the laptop nor the Xbox. There must be something I am missing here.

Also, I read somewhere that I might need a crossover cable instead of a patch cable... how can I tell the difference, and would I get another error instead of what I am getting if that was the case? (After all I can make a LAN connection to the Xbox!)