Celebrate the Magic (the castle projection) happens before the fireworks start. You would have time to move away from a closer viewing spot. If you do not want to see Fireworks at all, just head away into Adventureland or Tomorrowland, where the booms will be less prominent. Do not go into Fantasyland, as they are the loudest there. I'd recommend hanging out near Casey's Corner to watch CTM then heading to Adventureland if you want to skip Wishes. If you do want to see the fireworks, you can watch the fireworks from the Swiss Family Treehouse a distant and quieter view (the music won't be as easily heard though). You could also move further back down Main Street, but crowds might make that difficult.