These emails are bogus. Any ISP would send an abuse complaint to NTL - and they would inform you of your compromise - in accordance with their Acceptable Use Policy, this is the protocol for abuse complaints.
As has been said, delete and ignore the spam. More similar emails reported here:
http://www.thenetworkreloaded.com/vi...bcf2a8df8#8514
http://answers.yahoo.com/question/in...7094753AAJMwDc