Complex sentence: In June 2007, she was the guest star at the Marietta, Georgia Gone With the Wind Museum event "The Heart and History of Hollywood" with Turner Classic Movies (TCM) host Robert Osborne as emcee.
Split into simpler sentences: In June 2007, she was the guest star at the Marietta Gone With the Wind Museum in Marietta, Georgia. The occasion was "The Heart and History of Hollywood" event with Turner Classic Movies (TCM) host Robert Osborne serving as emcee.