Emmett was born in Gosford to Michael and Laraine Emmett and grew up in Umina Beach, on the Central Coast of New South Wales. She had three siblings named Matthew, Shane and Lesley. Emmett went to school at St John's at Woy Woy, St Joseph's at Gosford and Corpus Christi at Tuggerah.

Emmett worked at the local Coast Rock FM radio station and sang lead vocals in the band Big Baby Jam. In 1994 she gained her first major role on Australian television as Tracy Russell in the sitcom Hey Dad..!. In 1996 she joined Home and Away as Rebecca Fisher, where she earned nominations for Silver Logie for Most Popular Actress in 1998 and 1999, as well as a Gold Logie nomination in 1999.

Emmett was diagnosed with breast cancer in 1998, aged 24. She took a break from her role as Rebecca Fisher/Nash on Home and Away (during which time the part was played by Megan Connolly) and underwent surgery to remove a malignant tumour, followed by six weeks of radiotherapy. She left the cast of Home and Away the following year and went on to appear in nine episodes of All Saints as Jodi Horner between 2000 and 2001.

In September 2001, on the set of the Australian film The Nugget in which she co-starred as Cheryl with Eric Bana, Emmett began to experience intense back pain. Further tests revealed that the cancer had spread to her bones.

In 2002 she told Australian Women's Weekly that "It wasn't a matter of if, it was a matter of when. The little bastards were going to get me. It was a weird sensation, almost an out-of-body experience. I don't think I'll ever be able to explain it."[1] In an interview with Charles Wooley on 60 Minutes that same year, she said:

""I think people underestimate the power that they have within themselves, I really do, and I think these kinds of challenges, they force you to look that little bit deeper and see what you're really made of. I always knew I was pretty strong. I've always been pretty gutsy and pretty ballsy, but I think I surprised myself this time around." <i>

On January 29, 2005, Emmett married comedian and TV personality Rove McManus, at the Mary Immaculate Church in Waverley in the eastern part of Sydney. She walked down the aisle to Stevie Wonder's ballad "You Are the Sunshine of My Life". The couple had met at the opening of Fox Studios in Sydney in 1999. "We're kindred spirits," Emmett told a newspaper at the time.[3]. Guests included Marcia Hines, Stephen Curry, Merrick Watts and Peter Helliar. At their reception, the couple danced to Ben Folds' song "The Luckiest".

On November 11, 2006, just after dawn, Emmett died from cancer at St Vincent's Hospital in Sydney. She had been there since reportedly suffering "stroke-like symptoms" the previous Monday.[4][5] Prime Minister John Howard said he and Mrs Howard were saddened by Emmett's death. "She fought a very courageous battle against cancer," Howard said. "On behalf of Janette and myself, I extend my deepest sympathies to her husband, Rove McManus, and her family and friends."[4] Opposition Leader Kim Beazley also passed on his sympathies. "This is truly sad news which I think will affect all Australians," Beazley said. "The tenderness and care in their relationship (Rove and Belinda) through their adversity, I think, has been an inspiration to many, many Australians."