Ah. I just ran the boot repair and came back to find the update-grub messages. So I'll try that, but in the meantime here's the pastebin generated by...
Thanks for the help. So thinking I will shrink my windows partition to 386GB, 64GB for / and the rest for /home. But still not sure about a swap file...
The simplest thing to attempt to repair this problem is the update -grub suggestion above and if that does not succeed, get boot repair as suggested...