Daniel:
You are right, you should decide for yourself if the Witnesses teach the truth or not. I am a real Witness and enjoy being part of Jehovah's people.
Most of the people in this site are ex-witnesses and really hate the organization. It is unwise to listen to their negative comments. It's as if you were applying for a job and the employer wants to know your references in order see what kind of person you are. Would you give them a reference of a person that hates your guts? Of course not because it is biased and will probably exagerate anything that you've done in the past. No, the employer would want to hear from impartial folks that will give a true assessment of your abilities and personality.
It is the same in this case. The enemies of Jehovah's organization will not give any positive input. Study with Witnesses, ask questions, try to be logical and you will learn a lot about Jehovah's purpose and doing his will.
If you have any questions feel free to email me.