[Samba] simple recommendations

[Andy Smith]

Hi all, 

  I've used samba for years, but only really for simple scenarios where
a few files needed to be shared to PCs. I now need to configure a server
where, as far as is possible, it should behave like a Windows server. As
not all the PCs on the network have Windows Pro I won't be joining any
PCs to a domain. So my main question is, is there any reason to install
as an AD DC or should I install it as a standalone server? 

Where I say it should behave like a Windows server I'm mostly thinking
about the ability to set/modify file and folder permissions from PC
clients, is it ever possible to do this without using a PC domain
member? My experience of this is that it is not, ie if you try and add a
group that exists on the server from the PC it just gives an error so
permissions must be modified on the *NIX side. Would be good to know if
this is the expected behviour or if I've just not got things configured
correctly (I have this situation currently on a test install with a
Samba AD DC), 

thanks in advance, Andy.