How to get rid of "pending" orders?

[submissionfc]

For a pretty long time now when customers go through check out on my website and click "confirm purchase" they are then re directed to the paypal page where they must pay to finish the order. However, if they click "confirm purchase" and never pay they actually get an order # and their order is marked as "pending" and not "confirmed". So this makes some customers believe that they have finished processing the order even though they have not paid for the order.

How can I set it up where the customer must pay before they get an order # and so it is either a confirmed purchase that we process or there is no order at all. No "pending" orders anymore.