Here is a deck of slides that you should not miss when talking about player emotions and fun. Nicole Lazzaro‘s four fun keys should not be missing in any good game design collection for that matter. She runs a company called XEODesign, which does player experience design research. In her presentation, she talks about the 4 fun keys, namely hard fun (e.g., fiero), easy fun (e.g., curiosity), people fun (e.g., amusement), serious fun (e.g., relaxation). These fun keys were generated throughout a large number of interviews, lots of research and observations. They are discussed in the slides with vivid game design examples. Here goes her excellent presentation:

If you want to find out more, you should check out Nicole’s list of presentations and read her whitepaper “Why We Play Games: 4 Keys to More Emotion (PDF).”