After weeks of intense media speculation about Whitney Houston's health and career — following missed performances at the Rock and Roll Hall of Fame induction ceremony and the Oscars in March — the R&B diva is attempting to turn public attention back to her music.

She put out a four-record box set of unreleased dance mixes Tuesday, and a two-CD greatest hits package that includes four new tracks will come in mid-May.

According to Arista Records and Houston's independent publicist, Nancy Seltzer, the singer is planning no concert or television appearances to promote the releases, though a label spokesperson did say appearances were possible. After missing scheduled performances, Houston most recently sang a collection of her hits at Arista's 25th anniversary celebration April 10 in Los Angeles. That concert is scheduled to air May 15 on NBC.

The four-record box set, Whitney — The Unreleased Mixes, a vinyl-only collection, features eight extended dance remixes, including a Junior Vasquez mix of "How Will I Know" (1985) and a David Morales mix of "So Emotional" (1987). Also included are club versions of "I'm Every Woman" and "I Will Always Love You" (RealAudio excerpt of original version). The original versions first appeared on the soundtrack to Houston's 1992 movie, "The Bodyguard."

The collection "acknowledges the importance of Houston's music in clubs around the world," according to a statement from the singer's label.

Some of those remixes also appear on Whitney — The Greatest Hits, a two-CD, 36-track collection due May 16. Disc one, titled "Cool Down," focuses on ballads from the singer's 15-year career. Its 18 tracks include the album mixes of such Houston hits as "Saving All My Love For You" (1985) and "Run to You" (1993).

Disc one also includes "Same Script, Different Cast," a new duet with R&B singer Deborah Cox, and "Could I Have This Kiss Forever," a new collaboration with Latin-pop sensation Enrique Iglesias.

Disc two, titled "Throw Down," is composed of uptempo singles and dance mixes, some of which — including "How Will I Know" and "I'm Every Woman" — also appear on The Unreleased Mixes. It also features a Jonathan Peters' remix of 1999's "My Love Is Your Love" (RealAudio excerpt of original) and a Hex Hector remix of "Heartbreak Hotel" (1998), which also features R&B singers Faith Evans and Kelly Price.

The disc also includes two new versions of "If I Told You That," a song that originally appeared on Houston's 1998 album, My Love Is Your Love. The first, a duet with George Michael, was produced by Rodney Jerkins and Jon Douglas. The second is a remix of the album version of the song.

The other new track on Whitney — The Greatest Hits is a song called "Fine," mixed by former A Tribe Called Quest member Q-Tip, Lucy Pearl's Raphael Saadiq and rapper/producer DJ Quik.

In addition, disc two includes "One Moment in Time," which Houston recorded as a theme song for the 1988 Summer Olympics, and "The

Star-Spangled Banner," which she sang at Super Bowl XXV in 1991.

Fourteen of the songs on the collection reached #1 on the Billboard pop and/or R&B charts. Most of Houston's albums have gone multiplatinum, with The Bodyguard selling 17 million copies, and her 1985 self-titled debut selling 13 million.

Houston will release a video and DVD, also called Whitney — The Greatest Hits, on May 16. Among the 21 clips on both versions are several Houston music videos, including "How Will I Know" (1985) and "I Wanna Dance With Somebody" (1987). The DVD features the same videos, plus footage of Houston's television debut on "The Merv Griffin Show" in 1985 and "Impossible," from the Disney television special "Rogers & Hammerstein's Cinderella," in which she starred in 1997.

The DVD also will have interview footage and song lyrics.