How do i set up this portal-
 

How do i set up the portal/blog that is shown on this vbulletin forum using website http://www.virtualpetinsider.com/

They probably use something that's custom coded, if you're not much of a coder than I would recommend trying this: www.vbadvanced.com

Looks like they're using Joomla.

Well how do i set that up????

google "joomla vbulletin bridge" and you get this thread: https://vborg.vbsupport.ru/showthread.php?t=101761

It's not looks lile Joomla, it is Joomla :)
<meta name="description" content="Joomla! - the dynamic portal engine and content management system" />
Here you can download it free - http://joomla.org/. It's not a very simple CMS, but with a lot of free plugins and great customization possibilites. And as Lynne said, it's rather simple to integrate it with Vbulletin.

Yes, they are running a branded rocket theme template, so it's probably Joomla 1.5. You should be able to find a decent bridge somewhere in here to sinc logins also. I think the one listed will only work with 1.0+. If you can't find it here go create an account in the Jommla.org forums and you'll find several VB bridges in there. Joomla 1.5 has a fairly steep learning curve so I'd advise grabbing joomla-a users guide by North, it's a great help in setting it up and running it.