The Story of Philosophy by Will Durant is a good if slightly outdated intro. I also read Sophie's World and would recommend reading that first, but you can skip

The Story of Philosophy by Will Durant is a good if slightly outdated intro. I also read Sophie's World and would recommend reading that first, but you can skip it if you don't want to read fiction. If you want something that talks purely about ideas without reference to the famous names, Bertrand Russell's book The Problems of Philosophy is also good. It give a very good overview of the major questions that philosophy keeps coming back to without dwelling too much on the history of the different answers. He also gives his own opinions on some of these issues, but you don't have to take that too seriously.