There is a lot of focus from "energy food" companies about what to eat to maximize your performance. Greg Lemond has shared his perspective of the body as a furnace—just put it in and let it burn up. And some people advocate certain timing of your eating.
A recent article NY Times' article Real Thought for Food for Long Workouts talks about eating "real" foods rather than special energy or recovery foods, and questions the value of timing your eating.
The article is worth a read. The key point seems to be that following common, every day habits of eating healthy foods consumed throughout the day (for me, 3 meals plus 2-3 snacks a day) will yield excellent results. If energy foods make it easier for you to consume healthy foods on a regular schedule, they may be an asset to your diet. You probably don't need any of them, however, if you get breakfast, lunch, dinner, and some foods before and/or after exercise (more fuel near the times you burn fuel).