Reports in 1.3.5

I’m trying to run sales reports in a shop running 1.3.5



I need to set the parameters so that the report will deliver the following monthly report:



Products

Number of each products sold

Total value of each products sold

Number of orders processed.



The information needs to be based on processed/completed orders only (I assume this should be done using conditions but they seem impossible to apply).



At the moment the totals I get seem to include all orders (completed or otherwise) PLUS the figures double up. If one customer orders a product that is simple. If another customer orders two products this seems to get accounted for twice…



Any ideas… this is really urgent as my client is pressing me for accurate data.