Here's a quick to do list of things to do after you've installed Drupal.
Configure Post Settings (administer > content management > post settings)
Drupal has a defaul front page that is partially controlled by these settings. By default, posts on the front page are generally displayed as a "teaser" that shows only a certain amount of characters. On this page you can set the length of teaser posts as well as indicate how many posts will appear on the front page. You can also require users to preview their posts before publishing (a "preview" button appears, which renders the post as it would appear on the website, before the user can publish the post - useful if you want to make sure users edit their writing)
RSS Publishing (administer > content management > rss publishing)
This page allows you to configure the rss feed generated by your website (rss feeds allows subscribers to have updated content from your website delivered to them - very useful for blogs and other regularly produced content). RSS feeds will include the lastest content added to you website. Here you can indicate how many posts will be included in the feed and how feeds will be displayed (full text, teaser, or title only)
User Settings (administer > user management > user settings)
This page allows you to configure the registration process for new users. If you're planning on being the only person updating your website or you just want registration closed to the public, you should select "Only site administrators can create new user accounts." If you're planning on making a website that is open to the public, this page allows you to personalize the messages sent to new users.
Date and Time (administer > site configuration > date and time)
Here you should set the default time zone of you website to your timezone (montreal = -0500). You can allow users to configure thier own time zones (i'll usually disable this, just to cut down on the clutter) as well as set the default display settings for the date and time.
Input Formats (administer > site configuration > input formats)
An imput format is language used when entering text to create a post. This page allows you to set the default input format. Because some modules require it (like TinyMCE), I reccomend you set your default input format to "Full HTML".
Site Information (administer . site configuration > site information)
This page allows you to personalize your drupal website. It's required that you submit the name of your website and the primary email address. You are given the option of including a slogan, a mission and a footer message, but these are only displayed in certain themes. If you've created a story or page that you always want visitor to see when they first arrive on the website, this page also allows you to change your default front page.