Is there a way that, i could integrate my site with my vBulletin?
 

I would like to know, if there is a way to intergrate my site with my board, like basically, i would like a registration page on my main site, and a box saying how many users are online and what not...anyone have any suggestions?

Yes there's a way to do it, I've done it for mine (Not the way you want but it's perfectly possible). I use the vB Page script so vB powers the pages, and had several people do scripts (paid of course) for me to integrate into vB to power other sections - but within vB.

The vB Page script is free and can be found here at vBulletin.org just do a quick search :) I'm sure you'll figure the rest out and edit accordingly etc.