Open the file defaultcat.php and search for this line:
<h2><a href="<?php the_permalink() ?>" title="<?php printf(esc_attr__('Permanent Link to %s','eNews'), get_the_title()) ?>"><?php truncate_title(37); ?></a></h2>
Replace it by this:
<h2><a href="<?php the_permalink() ?>" title="<?php printf(esc_attr__('Permanent Link to %s','eNews'), get_the_title()) ?>"><?php the_title(); ?></a></h2>