Use the PagePeeker Screenshots module to display screenshots from websites

The probably easiest and fasted way to fetch and display screenshots from websites is to combine the PagePeeker Screenshots with the Link module. Just install and enable both of the modules, add a link field to the content type and select "Pagekeeper thumbnail" as display format (Manage Displays). You can choose between a free, a link-back and a paid version of PagePeeker.

Alternative modules:

Taxonomy: 

Drupal themes to be compared