The National Football League claimed 13 of the 15 most-watched television shows during fall programming as 225 million Americans tuned in to games, according to Nielsen Media Research. ESPN?s Monday Night Football accounted for 14 of the 15 most-watched shows on cable, averaging 12 million viewers, according to Nielsen statistics released yesterday by the league. During the 2007 fall television season, 11 of the top 15 shows were NFL games, compared with one of 15 in 2003. NBC?s Cowboys-Giants game on Dec. 14 was the most-watched Sunday Night Football game ever, attracting 23.1 million fans.