First of all, you need to decide, what type of product do you need. If you are selling a Book, and you want to show a drop down for BOOK COVER COLOR , then you can just do a SIMPLE PRODUCT and add the COVER COLOR as Custom Options. But if you are selling a CAR and you want to show a drop down for FUEL TYPE, then you will also need to define the number of cars available for each fuel type . So, for that, you will have to create CONFIGURABLE PRODUCT, so that you can define inventory for each attribute....