Stocks opened mostly higher Monday as investors await this week's Federal Reserve meeting, though the Nasdaq Composite edged lower after turning in its worst monthly performance since 2008. The Dow Jones Industrial Average DJIA, -0.02% rose 77 points, or 0.2%, while the S&P 500 SPX, +0.09% edged up 0.1%. The Nasdaq COMP, +0.73% was down less than 0.1% at 12,334.