New York said Del Zotto, a restricted free agent with New York, has signed a two-year deal worth a reported $2.5 million per season.
The former Rangers first-round draft choice recorded a pair of goals with eight assists in the 2012 playoffs during his postseason debut after a regular season in which he set career highs with 10 goals and 31 assists for 41 points.
Meanwhile, ex-Rangers blueliner Gilroy returns to the team on a one-year deal after spending 2011-12 with the Tampa Bay Lightning and Ottawa Senators.
He had a productive stint with the Connecticut Whale of the American Hockey League during the 113-day NHL lockout, logging six goals and nine assists in 34 games.
The Rangers and other NHL teams opened training camps Sunday, following Saturday's ratification of a new collective bargaining agreement by the players' union.
The camps will last through the week, followed on Jan. 19 with the start of a truncated, 48-game season concluding in late April.