Easiest way to create a graphical representation of Application Usage Report?
Presuming that you want to have a pie chart for each user, and you want to group by application, and by time spent with each, I would recommend using Excel to do so. In a nutshell:


Create a PivotChart for each user, with the data grouped as you prefer. In my exercise, I selected Application and Time. Highlight the columns, with the top row being the header, and select Insert | PivotChart. Check the fields to add to the report, in this case Application and Time.
You can configure your chart to your liking. I tend to add value labels to my pie chart slices.


You can see my crude, 5 minute example below.