Windows system32 folder

my computer recently crashed due to a virus i had in a system32 folder. i reformated, everything is back to normal except that everytime i boot up i get the system32 folder pop up and it says these files are hidden to keep your system operating properly. i really dont want someone to get on my computer and get into it, how do i solve this problem,,,,,,i want to just keep from that folder opening on start up.  PLZ HELP