This video leaves me with nagging feeling, the WMD weren't GWB first lies...
911 Loose Change 2nd Edition with extra footage - Google Video
Some of the things presented as facts are false (as for example a fire does weaken a building), some things can be explained differently (for example the "explosions" while the WTC collapses could be the inner structure of the building breaking apart).
You have to make up your own opinion. Don't believe everything you are told, whether by the goverment or by some conspiracy fanatic. It's not easy, sorting through the rubble, I know.