Which version of Windows?
If XP
HOW TO Reset Security Settings Back to the Defaults:
http://support.microsoft.com/kb/313222
HOW TO Take Ownership of a File or Folder in Windows XP:
http://support.microsoft.com/kb/3084211
Access is Denied Error Message When You Try to Open a Folder - Permissions:
support.microsoft.com/kb/810881
Description of File Sharing and Permissions in Windows XP (Q304040):
http://support.microsoft.com/support.../Q304/0/40.ASP
If you are using Vista, then you should be able to remove permissions by using the security tab on the folder itself and giving yourself admin permissions; if you are still having issues, then you could try to do the following
1. on the security tab, click advanced
2. In the window that appears you should see a list of users with permissions. at the bottom of this window you should see an "edit" button- click it
3. at the bottom of the resulting window remove the check mark next to the button that says "Include inheirtable permissions from the objects parent"-what this will do is is stop whatever permissions are being set above it in the hierarchy to stop, essentially stopping the permissions from going to things below that point
4. When you uncheck the first box you will get a prompt asking you to copy or remove the permissions- choose remove
5. click ok in all open windows and try again