Currently my site comment system is of disqus. Now i want to switch to facebook comment system without loosing older comments ?? suggest me.
There are several plugins available for this. One of them is Facebook Comments for WordPress But you can search and use the one you like.
I think that most popular is plugin "Facebook Comments for WordPress" available under following link: wordpress.org/extend/plugins/facebook-comments-for-wordpress/ regards
I would advise using a plugin, just incase your theme or WordPress version gets updated (depending on the files you edit)
go with the plugin.. it whould be much easier, also the plugin is SEO optimized, got that it... manually inserting is also fine but just inserting is not the thing, u have to look after many things.. imagine about if Facebook upgrades it algorithms, u need to manually do it again.. with the plugin u can just click upgrade.. and done.. ur up and running again.. good luck...
Use a plug-in called "Simple Facebook Connect". In my experience having done this a couple times, this plug-in is the best and easiest to set-up in your blog. I tried to post a link to the plug-in but it says live links are not available for me yet.
Yeah I use "Simple Facebook Connect" and it is very good for my website. I agree with Yojance on this! Do not try to integrate it without a plugin.