Site functionality problem

I want to remove Drupal so I can reinstall with a fresh clean install I have deleted all the files and I can't seem to get rid of the sites folder in order to start over I have went into my FTP hosting site dream host and tried to delete the files manually after continually changing the permissions names on all files and folders in the sites folder they still remain every time I changed the file permission it still won't let me delete it please can you help me out with this I have been searching for this answer for a couple of days now thank you