Thank you gents.
Old Speckled Aircrew - have renewed the DHCP Lease (whatever that is) and on first look, Safari appears to be better but Firefox is still doing it.
MacAshop - please could you give me a few more details as to how I go about it. Is that via a right click on the wifi icon and Network Preferences?
Thanks again for the assistance. One of the reasons I went for Apple is that folks said "it just works" - and it used to!
Cheers,
mcdhu