At last. The New York Giants got their first win of the season Monday night by holding Adrian Peterson in check and converting Minnesota mistakes into a 23-7 victory. The Giants began the season with six losses in which they were the team turning over the ball (minus-16 difference) while showing little penchant for playing defense. But against the Vikings (1-5), they were efficient enough, if not overwhelming, and had three takeaways to one lost fumble. Peterson, the league’s MVP last season and a 2,000-yard rusher, was held to 28 yards five days after his 2-year-old son was buried in South Dakota. The man accused in the death was indicted on second-degree murder and manslaughter charges, prosecutors said Monday.