The answer to your question depends on your definition of "good." After all, tasty and healthy are not always the same thing!
Personally, I think the Jolly Time Blast O Butter Theater Style is the best flavor for a movie-going style experience. It tastes like theater popcorn, only fresher and better. The company also has many flavors like Jalapeno Butter, Mallow Magic and Caramel Apple. 
For a healthier treat, you can try Orville Redenbacher's Natural Butter 50% Less Fat which is also available in minibags if you are snacking alone. Alternatively, Act II has a Light Butter option with generous servings and low fat. Whole Foods also has an organic option with a great buttery flavor and low sodium content. 
You can also experiment with making your own, which will save you money and give you control over the ingredients and flavor.