Question about creating a report of hours logged on timesheets not submitted vs all hours logged

Hi,

We're having an issue where a significant number of people have logged time on tasks but have not submitted their timesheets, and I was asked to develop a report that would enable us to get the total number of hours logged on tasks that are on timesheets that haven't been submitted. What's the best way to go about doing that? 

Also, question about what constitutes "Actual Hours"? Is this all hours logged, whether or not the timesheet was submitted or does it only get considered an "actual hour" once the timesheet is submitted? 

Thanks,

Fiona