Here's a pre-2001 video by a WTC visitor - who confirms what I also remember from when I went up on the rooftop - many years ago:
"Although most of the space in the World Trade Center complex was off-limits to the public, the South Tower featured an indoor and outdoor public observation area called Top of the World Trade Center Observatories on its 107th and 110th floors."
full link: http://www.youtube.com/watch?v=XQiqoI0QNwg
I also recall that it was a windy day - and the whole thing was swaying most alarmingly !
Viewing this I am immediately struck by the clarity and detail in every aspect of this video, likely shot on a small 1/3" CCD consumer/prosumer DV cam or possibly an analog camera. There is stark contrast between this video and the 9/11 videos shot by the broadcast cameras with their full 2/3" CCDs that evidently all had massive malfunctions in terms of focus and resolution that day.
Not to mention of course, the temporary ineptitude of the camera operators to frame and follow anything of actual interest and importance, aside from the limited perspectives required to drive the hopelessly fantastical narrative.