Sorted!
What a wally.
The correct answer is "You CAN have two routers operating two seperate PCs on the same BT phoneline".
I will explain what happened for the benefit of others...
I manage to buy a tower in the sales, but didn't have enough for a monitor etc.
So, when I got the tower home, I disconnected the main one (downstairs) and connected the new one. I then set up the tower for its first use and made a back up on disc. I was able to connect to the internet through my existing BT 210 Voyager router (Why? I don't know).
I ordered two BT Voyager 210 ADSL Routers (one spare) at a good price. Get an e-mail from selling appologising that he didn't see that I wanted and paid for two, he will send another on to me.
Anyway, first one arrives packaged in box. A few days later, I get the second Router in plastic mail bail, securely packged in Bubble wrap. This is this is the one that I opened and tested first.
After no joy, I took the other router out of the box, tried that and still nothing. After asking for help on here and conntacting the seller about them, I thought I would package them together in a bigger box.
Folded up small and on the very bottom of the box of the first one that I received, hidden under the power supply, is a typed instruction sheet. :Blushing
Seller, in the meantime had phoned my mobile (couldn't answer it at the time) and left a viocemail. (he also e-mailed too, fair play to him).
Anyway, read the instructions (even though my main one downstairs worked on the tower when I first had it and set it up, and so, I thought this one would too), Put the IP in the top address bar as instructed. Came on as connected and can now use the internet.
Ah, No - it wouldn't connect. Before this scren I should see a screen that asks for my ISP Username and Password. I did see it - for all of a nano second.
So I phones the seller and while gassing away to him on the "dog & bone" the Username and Password screen comes on and stays on.
I enter my ISP Username and Password and "Bob's your Aunty" on comes the internet - So they Weren't faulty after all. :Blushing
So I Appologised to him profusely and had a conversation about the hassle he gets from disrespectful members (not me) etc, before thanking him again and hanging up.
So it is not entirely my fault. O)
Thanks to you all that replied to this thread - I appreciate it.
Admin.
*Waiting to have the 'urine extracted out of me'*