Mario Lopez hosts the Miss Teen USA 2007 Pageant (7 p.m., NBC) live from Pasadena, Calif. The former host of “Pet Star” and “Saved by the Bell” alumnus hoofed his way to semifinalist status on “Dancing with the Stars” in 2006, losing out to former NFL great Emmitt Smith.

It’s time for Katie Blair, Miss Teen USA 2006, to pass off her tiara to a new winner chosen from candidates from all 50 states and the District of Columbia. The Montana native spent her year doing volunteer work for Sparrow Clubs, Best Buddies and Gay Men’s Health Crisis.

¢ For the first time in a week, the Disney Channel will not be repeating “High School Musical 2” in prime time. But customers of DirecTV can catch the popular musical sequel in high definition by tuning to DirecTV’s The 101 at 8 p.m. and 11 p.m.

¢ You don’t have to be a Republican to enjoy the movies of Ronald Reagan. Our 40th president spent decades in Hollywood, appearing in films both distinguished and forgettable. Turner Classic Movies will air 15 consecutive Reagan films, beginning with the 1937 drama “Love is on the Air” (5 a.m.).

Reagan’s cinematic efforts offered fodder for both his champions and detractors. He played the Gipper in the 1940 football biography “Knute Rockne, All American” (10:45 p.m.), and it provided him with an inspirational nickname that lasted a lifetime. His political opponents liked to point to the 1951 comedy “Bedtime for Bonzo” (7 p.m.), in which Reagan co-starred with a chimpanzee.

Of all of his films, Reagan preferred the 1942 melodrama “Kings Row” (8:30 p.m.), which offered him one of his meatiest roles. Reagan would use a line of dialogue from this film, “Where’s the Rest of Me?” as the title of his 1965 autobiography. The 1939 weepy “Dark Victory” (10:15 a.m.) belongs to Bettie Davis, but it features a fine performance by Reagan.

Tonight’s other highlights

• The Panthers host the Patriots in preseason football (7 p.m., CBS).
• A wounded police officer (Rob Schneider) exhibits strange behavior after an unorthodox surgery in the 2001 comedy “The Animal” (7 p.m., Fox).
• A hobbit (Elijah Wood) and his scruffy entourage join forces with a wizard (Ian McKellen) to fight evil in the 2001 fantasy “The Lord of the Rings: The Fellowship of the Ring” (7 p.m., TNT).
• Hiding out on “Doctor Who” (7 p.m., Sci Fi).
• The Whiskers clan claims new territory on “Meerkat Manor” (7:30 p.m., Animal Planet).
• Scheduled on “Expose” (9 p.m., PBS): Reporters expose abuse in prisons holding immigrants.
• Stars discuss their upcoming network series on “2007 Fall First Look” (8 p.m., TV Guide Network).
• A thrill-seeker bedevils Adrian on “Monk” (8 p.m., USA).
• Dog sleds take Les through Labrador on “Survivorman” (8 p.m., Discovery).
• Benson’s investigation raises the suspicions of a police captain (Kim Delaney) on “Law & Order: Special Victims Unit” (9 p.m., NBC).
• Scheduled on “20/20” (9 p.m., ABC): In a repeat report, John Stossel sets out to expose the “Cheap in America.” He cites wealthy people who give to charity and those who don’t and argues that we should all give more.
• Shepard Fairey and the Duke Spirit appear on “The Henry Rollins Show” (10 p.m., IFC).

Cult choice

The 2006 documentary “Shut up and Sing” (9 p.m., Starz) recalls the violent backlash against country stars the Dixie Chicks in 2003, the crusade to have them blacklisted from corporate radio and their more recent efforts to find a new audience.