Convert a Drupal 5 site to Drupal 7
From what I've read, going from D5 -> D6 -> D7 can be a pretty involved task.

These two pages suggest you may want to start with a clean install of D7, recreating your content types and  Views, then using Migrate module or a custom script to migrate the content/users. (The migration path from CCK to the Drupal 7 Fields is discussed here: http://drupal.org/node/1144136.)


http://drupal.org/upgrade
http://quicksketch.org/node/5739


I don't know how complex your setup is (how many Views, content types, and modules you have), but it's probably the case you are going to need a fair amount of work to bring your site into Drupal 7. 


The related question is https://drupal.stackexchange.com/questions/1420/migration-from-drupal-5-to-7.