Nothing so defines a year as its most popular song. Or video. Or download. Or whatever. “VH1 Top 20 Video Countdown” doubles the countdown and expands to two hours to showcase the “Top 40 Videos of 2009” (8 p.m., VH1).

Videos include Beyonce’s “Single Ladies”; Taylor Swift’s “Love Story”; Green Day’s “21 Guns” and songs by returning diva Whitney Houston as well as this year’s most annoying oddity, Lady Gaga.

Other featured artists include Katy Perry, Pink, Rob Thomas, Kings of Leon and The Fray.

• Australian actor Eric Bana, who has appeared in “Hulk,” “Troy” and the recent “Star Trek” directs his first film. And it’s about the love of his life, a 1974 Ford Falcon GT Coupe. “Love the Beast” (7 p.m., Speed) chronicles his 25-year relationship with his Australian-built car and stints at the demanding down-under road race known as the Targa Tasmania.

Not alone in his love for the smell of gasoline, Bana interviews fellow auto enthusiasts Jay Leno and Dr. Phil McGraw, who share some anecdotes about vehicles they’ve loved and lost.

• Proof that Santa does not ignore the bold-faced names “Oxygen’s 25iest: Hollywood’s Most Outrageous Holiday Gifts” (10 p.m., Oxygen) looks at the shopping lists and stocking stuffers of celebrities including Johnny Depp, Lady Gaga and Oprah.

Special attention is paid to celebrity couples and the presents exchanged between Jennifer Lopez and Marc Anthony, Seal and Heidi Klum and Justin Timberlake and Jessica Biel. No socks and ties here.

Tonight’s holiday highlights

• An innocent (Will Ferrell) born at the North Pole travels to New York to find his true father (James Caan) in the 2003 comedy “Elf” (6 p.m., USA).

• Tim Allen stars in the 1994 comedy “The Santa Clause” (6 p.m., Disney) followed by “The Santa Clause 2” (8 p.m., Disney) from 2002.

• Jimmy Durante narrates the 1969 cartoon “Frosty the Snowman” (7 p.m., CBS).

• Jonathan Winters and John Goodman lend their voices to “Frosty Returns” (7:30 p.m., CBS) from 1992.

• Chevy Chase reprises his Griswold character in the 1989 sequel “National Lampoon’s Christmas Vacation” (7 p.m., AMC).

• The children of a broken home (Cynthia Gibb and David Millbern) set a holiday parent-trap for their separated folks in the 2007 TV movie “An Accidental Christmas” (8 p.m., Lifetime).

• Keisha Castle-Hughes (“Whale Rider”) stars as Mary in 2006 biblical drama “The Nativity Story” (7 p.m. and 9 p.m., TNT).

Tonight’s other highlights

• Greg Kinnear stars in the dramatic 2006 adaptation of the nonfiction expose “Fast Food Nation” (6:15 p.m., IFC), directed by Richard Linklater.

• A garden becomes a crime scene on “Law & Order” (7 p.m., NBC).

• Victor is cut loose and Echo faces her worst nightmare on a two-hour “Dollhouse” (7 p.m., Fox).

• Ariel exhibits disturbing trends similar to a departed spirit on “Medium” (8 p.m., CBS).

• A scientist’s killer may be less, or more, than human on “Numb3rs” (9 p.m., CBS).