If you ever try to delete a file that says "You need permission to perform this action" even though you are admin and it still won't let you, you can delete it by doing the following:

Right-Click the File or Folder you wish to delete.
Click Properties.
Then click the Security Tab.
Click the Advanced button at the bottom of the security tab page.
Then Click Owner. (It should say your name or Administrator).
Then click "Ok" to take ownership.
Then you can successfully delete or move the file.