Can't get to windows update site

Hi,
I have just bought a HP Pavillion laptop and am trying to get to the windows
update site to update my patches. I am using XP media center edition with
SP2. I try to load up the MS update site (which is correct URL as I can go to
the same site on another PC) but I just get a completely blank page. I have
turned off the windows firewall and temporarily turned off Norton Internet
Security as well. I can get to other websites just fine.
Please help

Cheers
Shanno

I forgot to mention that when I try to connect to www.microsoft.com the
browser is extremely slow - just loaded the headers and after 2-3 min did not
even load the site. Other sites I have been to seem just fine so I am not
sure what is going on.
Thanks