Firstly install Drupal 7 thanks to your distribution or by hand. (Ubuntu 11.04 doesn't include Drupal 7, but Mageia 3 and 4 do.) If you have to install Drupal by hand, follow the 6 steps of the Installation guide. Don't insert any dot in the name of the directory you install Drupal in. We suggest /var/www/drupal7/ and we will suppose below that such is its name. The corresponding database name cannot contain contain spaces, slashes, nor dots. I'll suppose below it is "drupal7".