I have been having the same problem for months now. I keep giving up and then coming back a few weeks later to give it a go. I've bitten the bullet this morning and contacted Virgin Media over the phone this morning, the first call was hung up, and the second call was no help whatsoever.
To clarify, I am trying to register for My Virgin Media but am having the same problem as the original comment. Despite my e-mail address, account number and Area Code being 100% correct, I am unable to register. Every time I enter these details, on the first page, the screen simply refreshes.