This has been the summer of our discontent, DVD-wise. Another week is approaching with scant few releases that really get our juices flowing. In fact, this week, there's only one major theatrical release to speak of: 'Source Code.' Fortunately, 'Source Code' is a watchable, involving, thinking-person's film that pleased audiences and critics alike. Jake Gyllenhaal, Michelle Monaghan and Vera Farmiga all turn in top-notch performances, and director Duncan Jones, who brought us 2009's enigmatic and original 'Moon,' keeps a firm hand on the story arc and pace. Read on.