I got in a right mess with disabling plugins one way or another.
My site seemed to fail randomly and not one particular plugin seemed to cause it.
At one point it looked like Google Analytics, Then Jet Pack, then Scroll Back To Top...
So I deleted the lot and started with a new approach.
Using All-in-one WP Migration plugin I took a backup of my "Working" Wordpress managed website.
I then installed WP fresh on my new hosting and installed the all-in-one WP Migration plugin.
After a bit of a while struggling to get the backup to upload (I vave VERY slow upload speeds!) I found an alternative way to get the backup onto the server via FTP (That wasn't easy either, trying to upload a 34mb backup and it kept cutting out!) But eventually I'm there...
I now have an identical copy of my site and I'm just going through to get this back down to a base template.
But it works and runs at acceptable speeds! YES!
Thanks guys for your assistance...