Key PointsThe S&P 500 has delivered annualized returns of more than 15% for the past 10 years, and about 10% for the past 98 years.If you’re a long-term investor, buying more stocks during a stock market crash is almost always a good move -- because it means stocks are on sale.10 stocks we like better than S&P 500 Index › There's never an easier time to be an investor than during a big bull market. When stock prices are hitting all-time highs an…