"Gosh, Ron, who ever said that I am "limiting myself to two or three possiblities"?"

You did when you said "Ron, there are 2 general possibilities here. " You did not say that there were hundreds of possibilities, you limited it to two.

"It's people who cling only to the official version of 911 who are limiting themselves"
I agree 100%

"And where were the body remains of the passengers on the plane that is said to have hit the Pentagon? "
They found body remains and there are photographs of the remains.

"Did all those people who were on the hypothetical jet just...vanish into thin air? "
You make an ASSUMPTION that it was a hypothetical jet. That is a critical leap of faith that you need to make in order for the theory to work, especially in the face of overwhelming evidence to the contrary.

"When real commercial jets crash, no matter how hard they hit and how hot they burn, body remains are found scattered around afterward. Lots of them."
Aside from the fact that there WERE remains found, most commercial jet crashes occure AFTER the pilot makes attempts to save the flight - not when it is flying 500 miles an hour into a building.

"Have you ever noticed that the physical damage to the Pentagon looks a lot more like what might have been done by a cruise missile?"
Have you seen a lot of cruise missle damage into buildings? Have you also seen a lot of airplanes fly into buildings at that speed? Can you make a judgement based on personal experience and knowledge, or are you making an assumption based on what others have told you?

"There is no evidence in any photos I've seen of their having done so."
Look harder, but don't expect to find a lot. Again, for your theory to work you have to disregard the possible damage a jet flying at that speed straight into a building can cause.

You are also asking people to believe that a cruise missle would have been fired into the Pentagon during morning rush hour in Washington DC. Have you ever driven by the Pentagon? Do you realize how difficult that would be to pull off?

Nothing is impossible, but when you cling to theories that have the least probability of being true, you end up missing the truth.

Perhaps Shatner was flying the plane?