I'm in Bracknell - RG12. The problem seems to be the NTL DNS servers which are not pingable (i.e. they're both offline!
). Without DNS your PC does not know where
www.bbc.co.uk is (for example) because it needs the IP address - 212.58.224.88. DNS translates one to the other. The reason you are getting to some sites is that your PC has cached the DNS entries for those sites.
Thanks to my VPN to work I managed to get details of some other DNS servers you may want to try and use - 158.43.240.3 & 4 worked for me!