What I have learned over the years is that if you are looking for pure entertainment and laughs, Jim Carrey is a pretty good bet (movies that I recommend are The Truman Show, Fun With Dick and Jane, Bruce Almighty, Me, Myself and Irene, Dumb & Dumber, Ace Ventura: The Pet Detective, The Mask, Peggy Sue Got Married, and Earth Girls Are Easy). That is exactly how it turns out with Yes Man.Most of us have the problem that we can't say No when we really need to and keep getting into trouble trying to be civil, polite, and pleasant. Carl Allen (played by Carrey) has the other problem: not being able to say yes, until a friend convinces him to attend a talk by a motivational speaker Terrence Bundley (played by Terence Stamp) who helps people to discover the possibilities in life by saying Yes more often. Carl gets the message a bit jumbled up and says yes to everything. Disaster is bound to happen as probably Gandhi realized when he tried to experiment with truth.
As always, the very pretty (and with some of the most beautiful eyes) Allison (Zooey Deschanel) is charming as Carl's girlfriend.
The plot of the movie is not the most coherent but it is a movie that you can enjoy when you are in a mood to entertain yourself.