Hello,

I have one suggestion for blog comment, when logged-in user commenting on blog there is only option for Name and Comment.

You can add 2 more option

1. Email (optional) - you can skip this
2. Website  (But this is required - so that user comment for backlink)

Many website providing this option.. like Gizmochina - most popular website more than 6 million views in a month.

and if they post their website there - after approving comment by admin - Name is showing clickable like link with their website. when other users click on their name - their website open on new tab.

So please do this...

or tell me how can I do this - if possible. 

Letting people add backlinks on your site just for "free" is completely crazy idea that damage your site and is like welcome message for spammers.
So no, we does not integrate such feature.

ok... thanks for reply.

Please tell me one more thing,

But same option available for users to add their website address in user profile. Is that ok or I have to hide that ?

That require user registration and usually has "nofollow" on it.
Anyway for this one you have good options to control it.

Ok thanks for reply.

If it's no follow then this is good... I dont have to remove this website link option.