Let's look at this, shall we?
But basically, the string theory is the theory that's supposed to tie all four known forces in the universe together in one master equation (Gravity, Electromagnetism, and the strong and weak nuclear forces). 
There is no single string theory. In fact, there are many different string theories, that have been revealed to be different sides of the same underlying theory, called M-theory. The purpose is to unite quantum mechanics and general relativity into a united theory. It will likely include more than one equation. In fact, probably much more than one equation.
The laws of physics are much different on the nuclear level than they are on the big, universal scale(as explained by Einstein's theory of relativity). 
No, the laws of physics are the same everywhere. It is just that the effects of the laws of physics is different depending on the level you are on.
At the nuclear level, everything is unpredictable, and you can only measure the probability of something happening. 
If everything is unpredictable on the nuclear level, then there are no laws at the nuclear level, since laws imply predictability. There are laws at the nuclear level, or the quantum level, and they do make predictions, only probabilistic predictions.
It's basically, like the unifying force of the entire universe. 
At that level, there is no concept of force at all, just interactions between strings.
Apparantly, if the String Theory is true, spacetime has 11 dimensions, rather than the familiar 4 (the 4th dimension is time) and there could be millions of parallel universes right beside us. Don't ask me how that works. 
Simple - 11 dimensions imply 11 degrees of freedom, that is, you require 11 numbers to completely specify the position of something in space-time. The term you are looking for is multiverse.
I'm pretty sure that the String Theory says that time travel is theorectically possible. 
Wrong theory; that is the general theory of relativity. Technically, you are already traveling in time - by one second per second.
If the String Theory yields a universal equation for explaining everything, we could figure out lots of stuff, like about how the universe came about, what Black holes are really like, etc. 
Yup.
There's no way this theory can ever be proven one way or the other. There's no testable evidence, and there's no experiments or observations that can be made to prove it right or wrong. That's why many people refuse to call it science. It's more like philosophy. 
WRONG. You can predict all the masses of every particle a priori by M-theory, which can then be tested in things like the LHC. M-theory predicts supersymmetry. If supersymmetry is shown to be false, M-theory is also false. This fulfills Popper's demarcation criteria.
We talked about it in my physics class today, and some of the religious people got pretty upset by all of it, saying that the string theory was out to prove religion wrong and meddle in the affairs of God. 
Yes, religious people have no idea what they are talking about. What a surprise!
But the way I see it, if String Theory were true, wouldn't that actually help the idea of religion? I mean, I'm kind of a spiritual person, and I've always believed in a kind of universal energy that drives everything and everyone to do the things they do. Isn't God the same concept? A universal being, at the heart of everything. 
Energy is just the ability to perform physical work. No big magic here.
Maybe, godlike beings do actually exist in some of the parallel universes that would exist if String Theory is true, and sometimes cetain people can sense their presence, if some part of spacetime dividing the two universes is disrupted. 
Random speculation with no basis in science, or M-theory.
Entertaining, but epic fail.
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"The larger the island of knowledge, the longer the
shoreline of wonder" (Ralph W. Sockman)