When you right-click the folder, what permissions does it list for you? Look and see who had full permissions.. You can change the ownership of everything (as long as you are an admin) by right-clickng the active partition, clicking the security tab, and clicking advanced.
Oh, I assumed that you were running XP professional.. home edition does not have this property. Try this:
1. Restart your computer in Safe Mode. To do this, follow these steps:
* Restart your computer. Before you see the Windows XP logo, hold down the F8 key.
* Select Safe Mode.
2. Login in as Administrator. You'll get a warning about running in Safe Mode. Click Yes.
3. Find the folder whose permissions you wish to change. Right click on that folder, and select Properties.
4. Change the properties of the desired folders
If this still doesn't work, then there is one last thing that I know will work..