OK -so you have a good connection to the internet
and DNS is working
so something is blocking your access
lets try a clean boot
http://support.microsoft.com/kb/331796
if that works then
http://support.microsoft.com/kb/929135
and DNS is working
so something is blocking your access
lets try a clean boot
http://support.microsoft.com/kb/331796
if that works then
http://support.microsoft.com/kb/929135