If you do not like the built-in Take Screenshot application (under Applications, Accessories), then here is your new tool: GScrot !
http://gscrot.ubuntu-projekte.de/wp-content/uploads/releases/ubuntu_debs/ [5]
Links:
[1] http://pulse.veltsos.com/category/it/blogging
[2] http://pulse.veltsos.com/category/it/software
[3] http://pulse.veltsos.com/category/it/softwareoslinux
[4] http://linux.philosweb.com/drupal5/files/image_2_26.png
[5] http://gscrot.ubuntu-projekte.de/wp-content/uploads/releases/ubuntu_debs/