Can you create a calculated column in a Summary Report that uses other columns in the report to generate the final column?

At this time you cannot do calculations between columns on a Summary report.  The only way to do this would be to create a new table where the Key field was, for example,  the first day of each month going forwards or backwards for a bunch of months.  Then make a relationship back to that table with a formula field like

FirstDayOfTheMonth([Move Date])

 and Summarize the Total Hours and Total Moves.  Then  do your calculation on that monthly table.

If you need finer slicing and dicing I have some ideas on that too.