Just installed Drupal a few hours ago. Had some minor hiccups, that took a couple of minutes to solve and thought I should document it.
1. On visiting localhost/drupal, it asks for languages. I selected English and in the next step, it was unable to find a working database configuration. Since I was using mysql, the solution was to install the following
sudo aptitude install php5-mysql
and restart apache2
sudo /etc/init.d/apache2 restart
2. Drupal installs but on the admin page complains about cron not working. A manual cron run fixed that. There is a button right under in the drupal warning, so that was simple.
3. Drupal compains on the admin page about gd library not being installed. I recollect that it was a graphics library of some kind, so off I go to aptitude again.
sudo aptitude install php5-gd
and restart apache. Everything hunky-dory. Back to playing with drupal.