Thanks Matt - MySql problem now resolved, all due to user error of course!
I think theres a few games been played by my previous hosting company - in total I had nine accounts with them, and I closed down all nine. I told them not to close the domain I've transferred to Xilo.net until I was confident it was all moved across, but would you believe it - they have closed the account.
Thankfully, I had backed-up before moving, so no data lost, and all files loaded on to the server yesterday afternoon, but at the moment I'm getting an Error 403 page - sometimes you refresh it and the site appears.
Is this just part of the process, and in time it'll migrate across?