This is an interesting version of a sort of question that often comes in. It's a chance to talk a little about the philosophy of science, specifically what we mean by a "theory".
There are now amazingly accurate precise mathematical theories of gravity and electromagnetism, or more generally gravity, the electroweak force, and the chromodynamic (strong) nuclear force. These seem to be obeyed precisely under normal circumstances, although just knowing these basic rules isn't enough to tell us how something complicated will behave. The rules are so precise that we can follow out their logical consequences to circumstances far outside ordinary experience, enough to realize that at some point the rules for gravity (General Relativity) and the other forces (part of quantum mechanics) will run into conflict. So people are trying to construct a more general theory in which everything fits consistently into the same framework. If that ever succeeds, I suppose you could say that gravity etc. are all one force, just as we now say that electromagnetism and the weak nuclear force are unified.
I'm sorry if this sounds a little rough, but when a scientist reads your request for feedback on your theory, the first question to come to mind is "what theory?" is there even the beginning of an approach to a theory? For example, can you suggest some specific circumstances under which effects of the unification would be observable?
As for the specifics you raise- the magnetism of ordinary materials- that is routinely measured in many labs. There's a small diamagnetic (opposite to say iron) background in ordinary materials, plus some paramagnetism (the familiar sign) from a few unpaired electrons. There's also a little paramagnetism from nuclei, used for Magnetic Resonance Imaging. All this is well described by our current theories, in which gravity plays essentially no role.
No doubt this answer will seem unsatisfactory, so feel free to follow-up.
(published on 03/06/2011)