xBox Live conneting issuse

... So i'm kinda still new to this, so i may not be the sharpest tool in da shed, but here's da 411.
I signed-up for an Xbox live acc' i can log-on update my achievement points, download demos watch videos etc. When i got to try play my games ( ie Ghost Recon, Halo) on line i get a "Connection to live restricted" or something like that... type message. I looked around on the website but could find anything that i thought applied to me
What am i missing? How do i fix that? T'would be nice to jam online...