I won't ruin the movie (although there isn't much to ruin if you stay current on the news) but I will say it's an excellent movie. I tried to watch it rather critically, to see what faults people were going to find with the movie. Needless to say this movie isn't going to convince any one (that doesn't already believe) that Bush is a nutjob, but it does offer some interesting insights into his presidency and the war in Iraq. I believe that's all he's really trying to do. Just to raise awareness of how shady certain things are.
There's a very interesting segment in the movie where he tries to convince congressmen to enlist their children in the army. With a line like, "If you're so pro-war shouldn't you be the first to ship your children off?" He raises a lot of good points, and casts doubt as to the integrity of Bush, but again none of this should be news if you keep up at all. I enjoyed the movie a lot, it was emotional as well as humorous. I recommend it highly.
It should be noted that there is some graphic imagery in the movie, but then again it is a movie about war. It's nothing over the top, or without a serious point so I wasn't offended. Disturbed maybe, but that was the point.