Logging Users In - What is the Best Way

Okay Gents and Ladies, I am looking for more information on how best to do this. I have a MyQSL back end. It houses a users user_name and password. I have a secure area of the site that I only want members to view. The way I have it now is that the user logs in. If user_name and password match cookies are set. Each page in the secure are checks for a variable in the cookie. If set the user can view the page, if not set the page redirects back to the login page. Now first question is - how secure is this? Second question - what is a better more secure way to handle this. Then most importantly where do I get information on how to go about doing that? I know nothing about sessions and would need some good links for that arena. Also I do not know much of anything about Object Oriented Programming. Thanks for the feedback. Phillip