Clicked on update wordpress, server 500 error

Hello,
I’m a total noobie.

I had a fully working website with askimet and a fonts plugin.
Was told i had an update for wordpress, clicked it and now i cant even get to the dashboard.

When setting up wordpress i had added a parent folder by the request of some tutorial to stop hacking so my dashboard was at
http://www.simonconlon.com/gini/wp-admin/

When i try to access that or my site i get a server error 500.

I went to my host one.com and looked at the files. I could see that there were a bunch of files that were added recently (today) and one was a more recent index file inside the /gini/ folder.

I moved the old index file which was out side the /gini/ elsewhere and replaced it with the new index file, but to no avail, so i put everything back where it was.

Please explain any solution like you are speaking to a three year old.

Thanks in Advance.

Panicy Simon
http://www.simonconlon.com