These values represent the minimum length the value can be for a given field.
Values you can change in the Minimum option of the configuration menu
1.  Check stock level (Check to see if stock is available)
2.  Subtract stock (Entering true will decrement product stock when a product is order)
3.  Allow Checkout (Entering true will allow a customer to purchase an out of stock item)
4.  Mark product out of stock (Display something on screen so customer can see which product has insufficient stock)
5.  Stock Re-order level (Enter the quantity when a product will need to be re-ordered)

How To Change A Value
1.  Click on the name of the field you wish to edit.  It will change colors letting you know its selected.
2.  Click on the "Edit" button on the right side (see Figure-1)
3.  Make your changes
4.  Click on the "Update" button to save your changes (see Figure-2)

Figure-1 Click to enlarge

Figure-2 Click to enlarge