TONIGHT'S MUST-SEE

"Lost," 8 p.m., ABC. On the final night before a sweeps ratings period begins, many of the shows are reruns. Fortunately, "Lost" is rerunning a terrific episode. That's the one that told us about the amiable and (sometimes) oafish Hurley. We learn about his lottery win and its aftershocks. It's a strong hour with an emotional finale.

"The Color of Friendship" (2000, 8 p.m., Disney) and "That's What I'm Talking About" (8 p.m., TV Land). Here are two solid efforts. Disney reruns an excellent movie based on a true story: U.S. Rep. Ron Dellums (Carl Lumbley) agreed to host an exchange student from South Africa. He assumed she was black; instead, he met a perplexed, white teen who was startled to see a black person in power. Afterward, switch to TV Land for a fairly interesting talk show. Five witty people — Diahann Carroll, Harry Belafonte, Wayne Brady, Paul Mooney and novelist and writer Toure — discuss black-themed issues.

OF NOTE

"American Idol," 7 p.m., Fox. The auditions continue.

"The Biggest Loser: Family Edition," 8 p.m., NBC. It's the second half of a weight-loss battle between two restaurant-owning families.

"African-American Lives," 9 p.m., PBS; concludes Feb. 8. Henry Louis Gates Jr., the noted Harvard professor, uses DNA testing to trace his own roots and those of famous blacks including Oprah Winfrey and Quincy Jones.

"Law & Order," 9 p.m., NBC. This rerun brings back Richard Brooks as Paul Robinette. He's a lawyer for a nurse accused of malpractice.