Best and worst of Elvis, at 75

Hard to believe, but the same guy who recorded the masterpiece "Mystery Train" also gave us the maudlin "Old Shep." Remember that one? It's a tear-jerker about a boy and his dying dog.

Elvis Presley put everything he had into both songs, and his version of "Mystery Train" eclipses even Junior Parker's original as one of the greatest rock 'n' roll recordings. But even the King couldn't breathe life into a dog like "Shep."

Elvis was like that: the ruler of all he surveyed in one song, a misguided crooner in the next.

On the 75th anniversary of his birth (his birthday was Friday), Presley remains a monumental and monumentally perplexing figure. When he finally found his voice at Sun Studios in Memphis in 1954 (after more than a year of failed attempts there under the tutelage of producer Sam Phillips), he became one of the key figures in rock 'n' roll, and the type of celebrity icon who comes along only a few times a century.

No artist of the past 60 years covered a wider range of music, from gospel and Tin Pan Alley tunes to raw blues and bluegrass. Presley put the music of lounge crooner Dean Martin and R&B shouter Arthur Crudup on the same plane, because he loved both.

He had great taste in songwriters and stylists (Rodgers and Hart, Hank Williams, Ray Charles, Roy Brown, Bill Monroe), except when he didn't. Careers have been ruined by covering songs such as "Do the Clam," co-written by Dolores Fuller, ex-girlfriend of B-movie director Ed Wood Jr.: "Everybody's got that beat. Well, listen to those happy feet." But for Presley it was just another in a string of top-40 hits.

Presley died at 42 in 1977, but he left behind a trove of music that is continually recycled, refurbished, repackaged and resold to a public that apparently can't get enough of him.

Amid the hundreds of Presley recordings available, land mines abound. Although no collection should be without some of his music, there's plenty that should be avoided at all costs. Here are the dos and don'ts of Elvis music:

Elvis at his best

"Elvis Presley" (1956): Full-length debut remains a rock 'n' roll landmark, with every facet of the singer's music (except gospel) on display.

"For LP Fans Only" (1959): An odds-and-sods collection released while Elvis was in the Army, this is actually loaded with prime material from early in his career, including the landmark "Mystery Train."

"Elvis: NBC-TV Special" (1968): The loose yet mesmerizing nationally televised "comeback" that made the leather-clad Elvis, however briefly, relevant for a new generation of rock fans.

"Sunrise" (1999): Where it all began at Memphis' Sun Studios in 1953, the extraordinary combination of Scotty Moore's guitar, Bill Black's slap-back bass and Presley's voice, augmented by his fist pounding an acoustic guitar. This is not the first rock 'n' roll ever recorded by a long stretch, but this batch of recordings pushed it into the mainstream.

Elvis at his worst

"It Happened at the World's Fair" (1963): The Hollywood years in "Cotton Candy Land."

"Fun in Acapulco" (1963): The sound of Elvis phoning it in with songs such as "(There's) No Room to Rhumba in a Sports Car" and "The Bullfighter Was a Lady."

"Speedway" (1968): Another movie soundtrack turkey, with the bonus of Nancy Sinatra sashaying through "Your Groovy Self."