How to use the Charts module for creating charts using Views?
Here's what I used (running a brand new drupal 6.25 install):


Views 6.x-2.16
Views Calc 6.x-1.3 (required for Charts)
Charts 6.x-1.0


The Charts module comes with a few chart providers (SD Image Chart and Google Charts). You need to enable one of them in the module list to use in views. I enabled Google Charts for this example.

Then, I created a new view. I set the Style option to "Chart". To demo the chart, I just added a Node: Nid field and created some dummy nodes. The chart provider you selected will  render the chart in the preview for you. You can configure the Style Plugin settings and the fields to get the kind of chart you want.