Have you tried just a basic user account? Setting very specific rights is hard/impossible to do on a standalone machine. You should be able to grant various file access with little problem but dialup access will be harder if it doesn't work right off. A normal user should have access to the dialup but still be restricted enough to not be able to install/uninstall things.
Other than that I'm not sure, there might be a 3rd party app that will do the restriction that you desire.
Or just setup a domain controller in your house
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