[sjastro]

So, just comparing a non-rotating black hole and just your average star or massed body; what would be the governing factor which forces you to drop the Einstein Equation and adopt the Schwarzchild Metric, that is, where does GR break down...is it that the energy density (on the right side) goes to infinity and the Einstein Tensor (left side) cannot balance the whole equation or something?

The solutions to Einstein equations are the metrics themselves.
In the case of the Schwarzchild and Kerr metrics, these represent gravitational fields extended into empty space from a mass source (planet, star, black hole etc). As a result the energy density tensor is equal to zero. Hence the metrics are solutions to the Ricci tensor.

The Schwarzchild metric looks totally different from the Einstein Equation...it looks like a polar coordinate system, which would explain the non-rotation part. Also, I can see how the Kerr Metric came from he Schwarzchild Metric but it uses something I've never heard of, the Oblate Spheroid Coordinate system.

For rotating black hole there are two "event horizons." One is the familiar spherical event horizon associated with the Schwarzchild (non rotating black hole), the other is a flattened horizon that extends out from the black hole. The oblate spheroid coordinate system represents this flattened horizon.
Ever wondered why accretion disks exist around black holes instead of accretion spheres? Thats because the matter is swept up into this flattened horizon.

Interesting that a Schwarzchild black hole can have any mass, but is limited only by the the conditions of its formation. SO, that means a grain of sand can become a black hole, but only if the conditions are favorable in its formation.

Yes any object has a theoretical Schwarzchild radius, which is the radius required to shrink an object to a black hole. For example the Earth would need to be shrunk to the size of a ball of 0.89 cm radius to become a black hole. However there are no known physical processes that will shrink a grain of sand or the Earth to such dimensions.
That can only be achieved in the cores of massive stars when gravity eventually overcomes the energy produced by nucleur fusion.
Cosmic rays may possibly provide sufficient energy to produce mini black holes during collisions between particles.

So who's right here??? Scientists at the LHC have been claiming that if in the unlikely event that a tiny black hole was created in a collision, it would instantly collapse, yet here we have a statement saying (subject to initial conditions for its creation) ANY size Schwarzchild black hole can exist. So I wonder how much system energy is required to sustain a Schwarzchild black hole.

The black hole doesn't collapse but evaporates. This is an application of Quantum Field Theory (QFT) to Black Holes.
In QFT there is no such thing as a perfect vacuum, a vacuum contains energy. As a result virtual particle/antiparticle pairs can be created in a vacuum (this has been experimentally verified through the Casimir effect).

If a virtual pair is formed near the event horizon of a black hole, the negative virtual particle is invarably "pilfered" by the black hole while the positive particle escapes. This violates the conservation of energy and black hole must therefore radiate thermal energy back into space.

A Schwarzschild event horizon is therefore required to explain the evaporation of black holes.

Regards

Steven