So the package arrived, along with a text message to say the line had been activated. Virgin.net seemed to be on track to provide an easy DSL experience.
Oh dear! No way! First they managed to ignore my questions and sold me the wrong modem - a USB unit only suitable for one computer, not two with wi-fi networking as I had told them. This will require an ethernet modem (which I had assumed they would send). So now we await the opportunity to obtain the right modem.
Not overly detered, I decided to load the USB modem software and check that the line works. After a lot of trouble and three expensive calls to the technical support, I have found that the USB modem will only work through the BT service outlet. The regular phone cables within the house appear to be scrambling the DSL signal. The tech support people assure me this does not happen with an ethernet modem but I have to wonder.
There will be an acceptable solution eventually, I am sure of that, but meantime I am not getting any younger.
As to the connection speed, it's not too bad. I think the fastest download, on an iTunes podcast download, has been 60KB/s. I can live with that!