Where are login options stored? How can I read Login options from terminal (Automatic login, Display login windows as, Network Account Server etc.)?
Most of these settings are stored in /Library/Preferences/com.apple.loginwindow.plist. The "Show fast user switching menu" setting is stored at ~/Library/Preferences/com.apple.systemuiserver.plist (for each user account on the system).

The Network Account Server settings are stored in your Directory Services database. You can utilize the dscl command to look at various settings dealing with your Network Account Server. I recommend using man dscl to look at the details of this function, but as an example I can use the following command to see the Active Directory domain I'm bound to at work:

dscl localhost -ls /Active\ Directory

For Open Directory you would use:

dscl localhost -ls /LDAPv3

Additional Note from OP: .plist files are coded in binary. To read them in Terminal you will want to make a copy of the file that you can tinker with, and convert that copy into XML format. Use the cp command to create your copy and plutil -convert xm11 examplefile.plist to convert to readable XML.