No HTTP or SMTP connections but FTP and IMAP/s (993) ok

[#1]

My area was part of a BT outage yesterday,  The fault was allegedly fixed at 10pm last night.. however I still cannot browse the web or send email.
Router reports itself as connected.  Strangely I can connect to ftp sites or to my email (Imap over ssl on port 993).
Tried three different, previously working P.C.s all same problem.  Rebooted router and modem.
Anyone have any ideas?  @PlusNet could this still be part of a wider problem?
Thanks

[#2]

This may or may not be the problem - I am really guessing here
Could it be a DNS problem
If, instead of putting the normal site address in you put the IP address does it work
This is one of the IP addresses for www.google.co.uk ; 173.194.41.184

[#3]

Hi, thanks for the reply.
DNS lookups are fine. I can also ping google.co.uk
Outgoing SMTP connections are also "blocked".