Creating users with name and email

Normally php programers create a table 'users' with name and password. But
the real access will be done allways with the same (super)user and
password. This is less secure and a bad design, too.

So ich pass the user thru php to the database. But I want to have additional
entrys for my users like the full name und the e-mail address.

How will I handle this the best way in postgresql:

1. adding the new columns to pg_authid?

2. CREATE TABLE users (
email VARCHAR ) INHERITS (pg_authid);

3. CREATE TABLE users (
rolname VARCHAR REFERENCES pg_authid ( rolname ),
email VARCHAR );

4. ???