I'd suggest taking a basic, university-level physics course before trying to delve into quantum physics. Also, take some advanced math. There is no "lite" version of quantum physics, and there is no unified "quantum theory."
You obviously don't know the basic scientific method or the scientific definition of a theory, so you really should go out and learn the basics before delving into the more advanced. I'm not insulting you; I'm merely suggesting the proper course of action if you really wish to learn more about the subject. There's no silver bullet to learn a branch of physics.
BUT, since you asked, I'll do my best to try and clarify for you, if I can.
The Quantum Theory is the idea that nothing is real unless it is observed, correct?
Incorrect. Certain branches of quantum physics hold that an object exists purely as a wave function until something breaks the wave function by observing it. However, not all branches of quantum physics subscribe to this theory.
So, does this mean that we are all separate universes, essentially, and unless we observe an action (Be it by listening or reading about it, or actually observing it) it will never happen?
No. It means that everything in the universe exists as a wave function until the wave function is interrupted or broken down by an observer.
2nd, does the presence of other entities affect this? Obviously, if they were to observe it, it is most likely that you would in some way observe it as well, and the action be done, but if there are other entities, each ignoring the action, will they themselves inadvertently do something that will cause you to observe the action, and therefore have it take place?
The wave function is broken down by any observer.
3rd, does concious or subconcious thought affect this wide-spectrum of observation? It would seem that the mere knowledge of a presence of the action would be grounds for it to take place. Is this true?
There is no evidence, as far as I know, that human thought or knowledge has any effect on wave functions.
It does seem a bit absurd, as Einstein and Schroodinger believed, but according to others, Quantum Mechanics are the explanations for many things. In light of Schroodinger's example of the Quantum Theory, we cannot know that the cat will die unless we observe the experiment. However, we know of the experiment's presence, and therefore can alter the fate of the cat.
See above. Actual, physical interference is what changes things. This is known as Heisenberg Uncertainty. If you take measurements of a system, you must have interfered with that system in order to get those measurements, so the data you acquire will always come with a certain degree of uncertainty. This is only relevant on quantum scales, though. It mainly applies to measuring the position and momentum of a particle. Measuring one affects the other. On a scale like a baseball, though, the uncertainty of momentum and position is ridiculously small, so Newtonian mechanics does just fine.
Do we decrease the cat's chances for survival? Or are we observing a later pattern of probability, and therefore sealing its fate?
Perhaps. Perhaps not. We don't know.
If you flip a coin you can get either heads or tails. On the quantum level, it is possible to be in a state where the coin is both heads and tails. However, you could never see this "dual" coin. If you viewed it, then either the result of heads or tails would 'collapse' out, and you would see one of those: either heads or tails.
The quantum level deals with probabilities. Superposition is a state in which a particle has an equal probability of existing in 2 places. This also, if I'm not mistaken, derives from Heisenberg Uncertainty. Since the uncertainty principle is really only applicable to smaller scales, I, personally, don't see why superposition states should exist on macroscopic scales.
