Good luck, and try to relax.

Peanut butter is a pretty high fat food, which will slow digestion and if you have enough of it restrict peripheral blood flow for several hours, which isn't what you want for intense exercise. The banana sounds fine. My pre-race meal is mostly carbs, very low fat, just a little bit of protein, coffee, and water.

Is the race so far away that you need to get up so early?