Fantastic, thank you James!
Deactivating the theme has worked!
However… Now I have another problem!
The original theme I used was so out of date that when I did update everything the entire site went out of whack.
It was such a long time ago but I remember that I edited the style sheets in WP to get everything to work, do you know if it’s possible to retrieve the original information so I can paste it back in again?
(Keeping my fingers crossed!)