Bobbie mockingly pretends to call Halle Berry when Joey asks her if she can get Gina a stylist job, and asks if Gina can do her hair for the Oscars.
Halle Berry is an Oscar winning actress (for Monster's Ball) best known for her role as Storm in the X-Men trilogy and for being a Bond girl in Die Another Day.
The Oscars are the biggest, and arguably most important, awards show for the film industry. Every year Oscars are given out to actors and actresses with the best performances, as well as directors and writers and many other categories. It is a star studded event, usually attended by all of the big name A-list stars.