TONIGHT'S MUST-SEE

"The Sound of Music" (1965), 7 p.m., ABC. This film tops a weekend stuffed with family movies. Based loosely on a true story, it has a high-spirited young nun-to-be taking a job as governess to the seven children of a stern widower. Songs ensue, against the backdrop of the impending World War II. The story is so-so, but the songs by Richard Rodgers and Oscar Hammerstein soar beautifully, especially when sung by Julie Andrews. "Sound" won five Oscars, including best picture.

OF NOTE

"Snow" (2004), 9 a.m., ABC Family. A Christmas-movie marathon starts with this clever comedy about Santa's son (Tom Cavanagh) and an attractive zookeeper (Ashley Williams). It's followed by the fairly funny "Christmas Do-Over" (2006) at 11 a.m. and an Olivia Newton-John double-feature — "A Mom For Christmas" (1990) at 1 p.m. and then "Christmas Romance" (1994) at 3 p.m.

"Tsunami, The Aftermath," 4:15 p.m., HBO. This powerful miniseries was spread over two Sundays; here it is in one burst. It shows a wide range of people in Thailand — tourists, natives and officials — dealing with the effects the tsunami had on Thailand.

"Mary Poppins" (1964), 5 p.m., ABC Family. Here's another classic family musical. Andrews won an Oscar for best actress.

"Dateline," 7 p.m., NBC. Barring a late change, this will be a "To Catch a Predator" update, viewing pedophiles who use the Internet. Consider it a detour from the weekend's feel-good trend.

"The Unit," 8 p.m., CBS. In a tense and well-made hour, Bob is in peril in Africa after his identity is discovered.

"Law & Order," 9 p.m., NBC. Van Buren (S. Epatha Merkerson) becomes personally involved with the murder of someone who had previously been splashed by acid.

"Saturday Night Live," 10:30 p.m., NBC. Jack Black hosts, with Neil Young as musical guest.