The WTF here is that on Windows Home this is hard and on Windows Pro this is easy. Windows Home lacks the graphical interface to do it. You have to use "cacls.exe", which is a command line tool. That said, I head there is a patch which restores the graphical ACL editor. You evidently need to log in as Admin to make these ACL changes
Microsoft used to provide said patch to NT4 users and that same patch will work on XP Home. I've tried it. The link is now broken but it should still be available on other "mirror" sites.