It seems like the first few chapters are named after the people who wrote them, but I was wondering how the other titles were decided upon.
First, let's fix up some of your terminology. The thing you are calling "chapters" are generally referred to as "books". The Bible is composed of many different books written at different times at the hands of several human authors (although all inspired). Each book is then divided up into chapters and verses for easy reference. Secondly the "first few" books you refer to must be the ones of the New Testament (Mathew, Mark, etc). Those are called the "gospel" books and are those people's accounts of Jesus life and ministry. However those are not actually the first books in the bible, the entire Old Testament comes before that.
The OT starts out with Genesis (or Beginnings or Creation depending on language and translation) but is pretty obviously named after the theme: how the world got started and early stories of God's dealings with men. Likewise there are a number of other books named after the theme of their content, such as Acts or Chronicles or Judges or Psalms or Exodus. Other books are named after the people that wrote them, such as James or 1st Peter. This is also often the case for the OT books of prophecy such as Isaiah. A few books are named after the main character that features in the story, such as Job or Ruth. Some of the books were originally letters, and are usually named after the person they were addressed to such as Hebrews of Ephesians.
The names of the books themselves are not inspired and you will find that they often vary from translation to translation and even more so from language to language. They are just convenient names that we give to reference which book.