Feb 2 (Reuters) - Shares of videogame retailer GameStop Corp resumed trading on the New York Stock Exchange after being briefly halted following a 42% slump when the markets opened on Tuesday. The stock has been at the heart of a battle between amateur investors and Wall Street hedge funds in a social media-driven trading frenzy since last week. It was last down 49% at $115. (Reporting by Susan Mathew in Bengaluru; Editing by Arun Koyyur)