Hmmmm..... I'm a bit calmer now... I have discovered that somehow I managed to switch on an old (and defective) AVG firewall which blocks everything. I've disabled it and got my Zone Alarm running and I can now access the world wide web of lies as normal.
I've still got the problem with the new router, but I'll try Netgear for some help there. Sorry to have bothered you all!
Maybe one of the moderators could mark this as solved to save anyone the bother of reading it all???
Edited by the_moose, 31 December 2008 - 01:16 PM.