Grier, a cast member of In Living Color, is a good choice as a friend of Bob's. Even at his most sedate, Grier is more flamboyant than Duchovny, and brings his energy level up a notch. Driver, who can be both silly and serious, occasionally at the same time, plays Grace as a woman who can appeal to Bob's lighter and heavier sides. Grace's sister, Megan Dayton, is played by Bonnie Hunt, last seen as Tom Hanks' wife in The Green Mile. Hunt directs it without a trace of irony but a fair amount of realism.
Hunt takes the risk of laying the emotions on thick, but has the honesty to pull it off.
Even more so than most fairy tales, it's long on happy moments, without too many uncomfortable scenes. Regardless, it's an excellent date movie. Fox Mulder has been chasing aliens, ghouls, and wackos for years. He's a cynic through and through. But even cynics go on dates.