Give me a break. There have been tens of thousands of Jedi's. You can't judge the Jedi order and their ways because of a few bad seeds like Anakin and Dooku.
Everything the Jedi stand for is what is right in the world. They are completely pure hearted, and good intentioned. But power corrupts, and knowledge of the force and how to manipulate it is power. Of course a few Jedi's are going to fall to the dark side when they get a taste of that power and what they can do with it. But that certainly doesn't mean that what the Jedi stand for, and their code and way of life is in any way flawed.
The only lesson you can possibly learn from that is that Jedi's should aspire to become more like Yoda and Obi wan, and less like Anakin and Dooku.