There is no way to objectively measure how useful a product is to all people since different people assign different levels of utility to different things. Any listing according to usefulness will reflect the value that the person making the list puts on the product. Here is one example:
Most useful category: books. I enjoy reading and therefore I like to buy books. They give me pleasure so I find them useful.
Second most useful: clothes. Clothes are necessary, of course. However, I do not care much for fashion so I attach little value to clothes.
Least useful: jewelry. I own no jewelry other than my wedding ring and my wife and kids don't much like jewelry either. Therefore, this has little utility for me.
All of these categories of products are sold in malls.