Disqus commenting system can be easily installed with Blogger platform and its commenting system is definitely more professional looking than Blogger inherent commenting system.
Disqus has given beautiful explanations for commenting system installation and one can access those details by clicking following links:
Automatic Disqus Platform Installation for Blogger
You will want to use their installation instructions here http://indian-share-tips.disqus.com/admin/settings/blogger/ (actually here the link is shown for our website and when you open your account and add your site; the link will be appearing with your site name)
Manual Disqus Platform Installation for Blogger
If you cannot install Disqus using this automatic installation, you can manually install Disqus using their manual instructions here http://help.disqus.com/customer/portal/articles/888340-manually-adding-a-disqus-gadget-to-blogger
Its comments can be synchronised with Blogger platform.
How one can contact Disqus?