You may be able to use your current router using PPPoE however, most routers we have bought for ADSL do this over the ADSL port which again is useless regarding connecting to the VDSL modem (a simple check, your "input" needs to be RJ45 and not RJ11 though also refer to router docs).
There is however a workaround
Basically, you need to downgrade the current HH3 firmware and telnet the HH3 with instructions to enable the input of a non-BT username.
I would post how to do this but I'm unsure whether I would be in breach of any TOS or whatever so my advice is to search the net for "HH3 hack" and there is a man who can.
I will invest in a decent router though as the wireless on the HH3 is dire. But at least I'm up and away ... happy hunting