I was wondering if there is such a person as a Jewish fundamentalist, the way that there are those folks in Christianity and Islam? If so, what percent of Jews would or could be classified as Fundamentalist? And, what would their core beliefs be?
I'm not sure what your definition of fundamentalism is. I've heard a number of definitions of the term, and my feeling is that it means different things to different people. So instead of getting into an academic discussion about literalism versus figuratism, let's talk about what bothers most people about the term, and see if Judaism has anything that fits the mold.
Personally, when I hear the term "fundamentalist" used pejoratively, the picture that comes to mind is a group of people who believe that theirs is the only true path, and that anyone who does not follow their way is evil. A group which sees only two options for the rest of humanity - join us or suffer the consequences.
This is not the same as being an "extremist." There are those who are passionate or even extreme about their own beliefs, whether a born-again Christian, devout Muslim, radical liberal or die-hard atheist. We can debate the pros and cons of each of these belief systems, but a strong conviction alone doesn't necessarily make you intolerant of others. It is when you cannot accept that there may be another road to truth, that not everyone has to become exactly like you in order to be a good person - that is when you start to pose a danger to the planet.
So is Judaism "fundamentalist" in this sense? Quite simply, we don't believe that Judaism is for everyone. Jewish thought is comfortable with the belief that there are many paths to G‑d. Our Torah outlines the 613 precepts that define the path for Jews, and non-Jews can find Him in different ways. They can live a moral and good life without keeping the laws which our religion prescribes for the Jew. Anyone can join Judaism by converting, but this is not necessary - a non-Jew can be fulfilled, close to G‑d, and earn a place in heaven without becoming Jewish. I think it is this universalistic approach that has saved Judaism from the plague of intolerance.
Don't get me wrong - there are certainly Jewish extremists, troublemakers and whackos. But I don't know of any significant group of Jews who are out to convert the entire world to Judaism or to stamp all out non-Jewish religions. Judaism poses a challenge to the such a person: If you really love G‑d so much, shouldn't you also love all His children, who are created in His image?