Looks like you were probably hit with the Revslider vulnerability. Be sure to use the most recent version of Revslider if you do want to use that plugin again.
As for the images, try changing them to 644 permissions like Bill mentioned.
You'll also want to import your old database to get all your posts/pages/users back. Revslider infections do not tend to affect the database so I hunch that won't be a problem.