Exclamation mark overload!!!!!!
I would think after all the advice so far you've probably got it going now, but just in case you need a sixth opinion, then yes sounds like you are plugging yourself into the composite.
The plugs on the Xbox component lead are colour coded to match red, green and blue. There will be component inputs on your TV also with red, green and blue and you ened to match these up. I think there's a switch on the component lead too, make sure that is set to HD. FInally you have to remember that component isn't like having something plugged into a scart, the TV won't auto change to an AV channel, you'll have to select the component source on your controls.