I want to implement comments for every post on my site. Is there any other easier way i can do this without using the default Wordpress comment feature?
IntenseDebate, Disqus and JS-Kit ECHO are all great drop-in comment systems. Any of the three is as simple as pasting a code snippet into your template. They also allow Facebook, Twitter, and other social network integration.
I personally use Disqus on several sites, and can vouch for its ease of use and awesomeness. JS-Kit is relatively new to the game, but comes with a bunch of great new features and seems a bit smoother to use.
Check out all three and decide which will work best for you. Disqus and JS-Kit each have live demos on their homepage. It's trivial to find a site running IntenseDebate if you want to test that as well.