Figuring out the answer to your question is a difficult one. My advice is to write about what you are passionate about and that you are interested in. By all means look at others hubs to learn from them, but going out looking for topics that generate high views is like searching for the Holy Grail, you will spend so long searching you will never start doing.
My advice is to start writing and publishing, follow the Style Tips and Goals when editing your hubs and read all the excellent information here on HubPages in the Learning Centre. Hop some hubs to get an feeling for what makes a great hub. This is what I did when I started. My first hubs were awful and got very low views and low scores. But I kept learning and growing and now have hubs with very high scores that are Editors Choice hubs. Good luck and happy Hubbing!