Right, i've had a look around to establish what I need. The domain name that the NE Forums is hosted on is with Easily.co.uk, who I've used for several years and they are v. reliable.
So, i'll be creating a web hosting account with them. I then intend to move the board to a phpbb system (as recommended by MrKD) which will give total independence and take out Proboards, who's service has gone downhill rapidly in the last couple of months, with servers overloaded, outages etc.
I'd like to transfer all users with all posts to the new board, but I don't think there's any other way of doing that than the long way. So i'll be making a start shortly.
Linkback: http://www.northeastforum.co.uk/index.php?topic=231.0