The Answer to this question is that, its easily possible to setup a Private Membership Based Blog in WordPress using the options which come within the CMS. First of all you need to need to Lock your Complete Blog from visitors direct access and for this you need to edit some wordpress files and permissions, but there is one wordpress plugin called as ‘Members Only.
Members Only is a WordPress plugin that allows you to make your blog only view able to visitors that are logged in. If a visitor is not logged in, they will be redirected either to the WordPress login page or a page of your choice. Once logged in they can be redirected back to the page that they originally requested. You can also protect your feeds whilst allowing registered user access to them by using Feed Keys. Checking the Members Only option below will make your blog only view able to users that are logged in. If a visitor is not logged in, they will be redirected to the WordPress login page or a page that you can specify. Once logged in they can be redirected back to the page that they originally requested if you choose to.
Members Only can also protect your blog’s feeds either by requiring a user to be logged in, or using Feed Keys. Feed Keys are unique 32bit keys that are created for every user on your site. This allows each user on your site to access your feeds using their own unique URL, so you can protect your feeds whilst still allowing your users to use other methods, such as feed readers, to access your feeds. Your users can also find their Feed Key in their profile page, and you can allow them to reset their Feed Keys if you choose.
Once you activate the settings you will have option to Redirect the Visitor to either the Login Page or any Specific Page. Once the visitor logges in you can redirect them to the Front Page of the Blog giving them access to everything. This is a excellent option available in the Members Only Plugin Options which you need to setup one time. Thats it this option gives you a complete private blog with access to only members.
There is one final setting to be configured which would allow you to enable visitors to become a part of your blog by registering, and for this you need to go to WordPress Dashboard > General Settings > Membership > Anyone Can Register. Click on the Checkbox to Yes and thats it you have completed the whole process.