R and RW Groups for Folders in a Volume

[KnightOfNih]

Hi All
First time FreeNAS user here. i have just built my baby and am excited to start using it.
I am a little confused with the best was to setup storage, users and security on my folders.

I plan to have a structure as follows

• ZFS Raid Volume
  - Media (everyone on network can read, admin to read/write)
  - Backups (only admin can read/write )
  - Z Drive (everyone on network can read, admin to read/write)

I will map to volume with my windows10 machine and ill connect with the admin account.
I also plan to be able to access the Media and Z Drive folders with my TV and/or Tablet (is this read only user account achievable without a password?)

Any advice on how i should configure my storage, users and security is greatly appreciated.