Well, that's not a board that stopped it from moving, that's the sound board. Removing that whole board will only remove the sound.
FWIW, I can see the bridge rectifier has smoked, I've been successful in the past at fixing some of those.
Here's the parts breakdown for the 6-82800 Locomotive: Lionel 6-82800 Parts Breakdown
From that list, this is the board You're looking at.