|Just a tip for "after" you've got this sorted out.|
It is best to put it back to "hide protected operating system files". The reason is that system files can sometimes appear in user areas. They can get in the way and should not be deleted.
It is useful to show hidden files and extensions so these two changes can be kept in place.
I've not run into "show the contents of system folder" (maybe XP Pro) but safest bet is to restore it to how you found it unless anyone else comments.
Google is NOT the only Search Engine!