Secure Login Form

[Jonathan Askew JBASKEW <JBASKEW () uncg edu>]

First of all, I have very limited experience with web development and
programming. That being said, I have been tasked with creating a secure
login form. What I need to accomplish is the following:

1.the user registers their user name and password, and then provides an
access code to prove they have bought the product and should have access to
the site.
2. The user then enters their username/password into the form in order to
login.
3. Upon returning to the site, the username and password should be
remembered and the user should not have to enter these again.

I have been looking at various ways to create the login from (php,
javascript, etc.) but I am concerned about the security provided. For
example, the simple examples of javascript logins expose the password by
looking at the page source. Since I am a new to web development, I do not
feel confident enough to create my own form. Each user needs to have their
own unique username/pass combo as well. Can anyone suggest some examples or
point me to a resource to get me started?

Also, this site has not been built yet and this is the first thing they
want done. I need some ideas for generating the access code and then
keeping track of which code has been assigned to which user. I was thinking
of using a random number generator to assign the codes. I am assuming this
will also mean that I need a secure way of checking the database for the
code and returning the data? Should https be implemented here?

Thanks in advance for any advice offered. Being new to these technologies,
I thought I should run everything by those more seasoned.

Blake