Target Corp. will expand its toy departments at hundreds of stores nationwide and improve its online toy-buying experience, the latest moves by the company to seize the holiday-presents market put in play by the bankruptcy of Toys R Us. Minneapolis-based Target (NYSE: TGT) outlined its plans on its company blog this week, promising to turn over an additional 250,000 square feet of space to its toy departments ahead of the holiday season — its first without Toys R Us as a competitor.