You should always update to the latest version of Drupal to take advantage of updates and to also guard your site's security. It's not a difficult process, but there are quite a few steps if you want to avoid errors and get it right the first time. This tutorial shows you every step involved.
If you use Drupal regularly, this will happen to you at some point. However, one of the good things about using Drupal is there are so many other users that someone else may well have found and solved the error.