Stylish Popular Posts creates a widget which displays popular posts based on the number of comments.
This is a very simple, easy to use plugin which creates a widget that can be used to display popular posts with thumbnails based on the number of comments. Users can choose how many posts they want to show in the widget settings.
Your Theme must support widgets in order to use this plugin. Visit WordPress Widgets for more details.
This plugin uses custom thumbnails, you can use Regenerate Thumbnails to regenerate the thumbnails for your image attachments.
To translate the plugin to a particular language, use the file provided in /languages/ folder.