South Park: Bigger, Longer and Uncut's most outrageous (and creative) aspect is in the use of "obscene" language. Unlike Austin Powers which takes greater risks and makes fun of non-so-politically correct topics (as illustrated by the Fat Bastard character), the film takes very little risks and engages in fairly politically-correct socio-political commentary. Fortunately the humour is so extremely inventive and novel that it kept me amused throughout.
The plot, as it were, is simple: Canadian film-makers Terrence and Philip introduce to the children of a little redneck town, South Park, how to combine profanities in the most novel of ways. The censorship-happy mothers of the children decide to have Terrence and Philip executed and wage war against Canada. It's up to the kids to stop it because if a drop of Terrence and Philip's blood touches the ground, Satan and Saddam Hussein will rule the planet for two million years.
As is the case in many films that try to shock and outrage, the plot is just a means to showcase many gags by creators Trey Parker and Matt Stone. In this film's case, the plot is also used to indulge in some clever barbs at various not-very popular ideas and themes in our pop-culture. The targets include Christianity, Saddam Hussein, God, censorship, moralism, war, racism, rural towns, parental neglect of children, Bill Gates, and many more.
One of the funniest scenes in the movie was the general leading the war against Canada asking all the blacks to be human shields. When Chef (Issac Hayes) asks the general "have you heard about the emancipation proclamation?", the general replies "I don't listen to hip-hop." There are many other clever aspects to this film: The use of a V-chip implanted into Cartman (Trey Parker) which gives him a shock every time he swears is strikingly Orwellian. The creation of Mothers Against Canada and subsequent knee-jerk reactions are a way of showing how the U.S. society as a whole tends to place responsibility for social problems on the symptoms but not its cause. Satan, the ruler of hell is a homosexual in love with Saddam Hussein (who just wants Satan for sex), a comment about recent comments made by the religious right.
The movie is structured as a musical of sorts (obviously a parody of the Disney-style animated films which works incredibly well), and while the songs were okay I'd have preferred to hear Primus or the other bands from the Chef Aid: The South Park Album be part of the scores. There are some interesting cameos by Brent Spiner (Data on Star Trek: The Next Generation), George Clooney, and Minnie Driver.
An interesting point to note about the animation is that even though it's so crude, while watching South Park, the quality doesn't detract from the show or the film. The expressions on the characters, their actions, etc. are readily identifiable and empathisable. So perhaps creating a successful animation with "poor" quality is a virtue in and of itself.
South Park is a phenomenon that has to be be experienced to be understood, particularly for the stunning animation. I highly recommend it.