You need to learn how to use the security tab. To see the security tab, go to control panel and open Folder options. click on the View Tab and scroll down to where it says "Use Simple File Sharing (Recommended)." Uncheck that one. then click OK.
Now you should be able to see the security tab when you right click on a folder and click properties. When you are at the security tab. you should see the permissions for the users. Now in your case just click on all the users and click remove. And then click and type in your name. then click on the permission that you want to have.
Now get this...NTFS file are permissions are kinda sensitive so dont mess with them unless you know what you are doing. I learnt it the had way. Of course if you are the administrator you can always replace the permsiions on any file or folder. Read more on NTFS File Sharing in google. Check out these websites for more info and help.
Hope this helps.