In 1994, Jen got her first break. She audition first for the role of Monica Geller, but later decided she would be better as the character Rachel Green. The show also stared Courteney Cox Arquette who played Monica, Lisa Kudrow she played Phoebe, Matt LeBlanc he played Joey, Matthew Perry, who played Chandler and David Schwimmer, played Ross. The show was a half-hour comedy with six friends who faced life and love in New York City. No one knew it was going to be big, until the first show. The show was so big that they had ten seasons. The actors on the show made 750, 000 dollars per episode, each.

Jennifer stared in the movie Along Came Polly in 2004. Jennifer played a character named Polly Prince. The movie is about a man, Ben Stiller's character,   who's afraid of a risk, and he gets married. On his honeymoon he finds out that his wife is cheating on him. Then he goes to a party and hooks up with Jen's character. The movie wasn't rated that well, though. She did make 5, 000, 000 dollars to play her character.

Jennifer also did a movie called Bruce Almighty in 2003, with the actors, Jim Carrey and Morgan Freeman. This movie is about a guy who complains about God, and he is given God's power to see how difficult is to run the world. Jen played Bruce's (Jim Carrey) girlfriend, Grace. The movie did very well in the theater. She was filming her show Friends, Along Came Polly and Bruce Almighty at the same time.

Jen also did a movie called The Good Girl. It was made in 2002. She played a girl named Justine. It did pretty well in the theaters. It's about a girl a girl who's unhappy with her marriage and ends up cheating on her husband. She gets pregnant by her co-worker and it all goes down hill from there. She made 4,000, 000 dollars when she made this movie. It did very well in the theaters.

Jen also started in the movie Object of My Affection. It was made in 1998. The movie stared Jennifer Aniston, Paul Rudd played a character named George, Alan Alda played a character named Sidney, and Timothy Daly plays a character named Robert. Jennifer played a character named Nina. This movie is mainly about relationship problems between Jen's character. It did well in the theaters. Jen made 3,000,000 dollars for her character in this movie.

Jen started in a movie called Picture Perfect. This movie was made in 1997. It stared Jay Mohr who played Nick, Kevin Bacon who played Sam, and Jennifer. Her character's name was Kate. The movie is about Kate who met a man she likes a lot, but in order to see if he really likes her, she hires an actor to make him jealous. Nick , the actor she hires, falls for Kate. She made 2,000,000 dollars for this film. This movie did great in theaters.