Jen Taylor
From Halopedia, the Halo wiki
Jen Taylor (or Jenn Taylor) provides the voice of Cortana in Halo: Combat Evolved, Halo 2 and Halo 3. She was born on February 17, 1973 in Seattle, Washington, USA.
Jen Taylor is best known for her work as Princess Peach, Toad, Toadette and other characters in several Nintendo games since 1999, and the voice behind Cate Archer in No One Lives Forever 2. In 2004, she also appeared in the feature film Inheritance. She also has done voice-overs for the PC game Aliens Versus Predator 2 with David Scully.