When I share files to my home group, I find the the other users are prompted to enter my username/password to access my resource. Is there any way to avoid this?
You do not need to edit any group policies. Read this tutorial and go to the Configure HomeGroup Connections section. How to Customize Network Sharing Settings in Windows 7
Most probably, your computer is set to "Use user accounts and passwords to connect to other computers" instead of letting Windows to manage homegroup connections.