***Lets assume for a moment that a God is there who is resposible for making all things happen in the universe. Then: Is the God, a natural or supernatural being? Stephen [H]awking referred to the 'God of order', I guess.***
My perspective is different. I don't see this cut-off between philosophy and science. Philosophy merges into science and science merges into philosophy. There is no absolute 'scientific method'. This is a myth. There are methods to science that have been very successful (e.g., H-T method, inductive method, deductive method, inference to the best explanation, etc). Some of those methods involve similar methods as used in philosophy (e.g., Occam's razor which was invented by a philosopher - Ockham in the 11th century in his attempt to rationalize nominalism over platonism).
With this in mind, when seeking an ontological basis to the world we need to justify our models whether they be philosophical or scientific. If possible, we need to 'test' them with thought experiments and in the case of science with real observable experiments. If the 'test' is successful we can give more weight to the model's validity, and if the 'test' is unsuccessful we begin to discount the validity of a particular model.
In the case of theism, what is being postulated is an underlying non-material order to the universe. The degree and boundries of that order is what is under discussion. You don't want to advocate more order or wider boundaries than is what is necessary based on the philosophical/scientific evidence (i.e., principle of parsimony).
It is a very lengthy discussion in finding suitable theistic models, and even more lengthy in analyzing these models in comparison to models that don't require underlying order to the world.
****Which religious dogma should one follow after believing firmly in God? Which moral system, in your opinion, is the best to follow?***
This all depends on the theistic model that one advocates. A purely mathematical model of underlying order (which I think falls into a theistic category) may require no morality among humans.
Generally being specific as to which religion is outside the limits of a purely philosophical inquiry. Religions rely on revelation, and without acceptance of revelation there is no way to stipulate a particular morality other than what is consistent with our human society (and that for pragmatic reasons). I've heard that Hawking has given his opinion that morality should be ordered like a mathematical order, but I don't think he would go any further by saying how or even why.
***Once you assert the existence of God, you face another disgusting flood of philosophical problems. Any permanent solution to these problems (as history tells us) is impossible to achieve. See, the flood gates are opened once again.***
They are only floodgates if we make them so. Remember, our primary task is to achieve a consistent rendering of science and philosophy as we see observed. If we start trying to decide doctrines of religions then we are either speculating or we are relying on the revelation of that religion. I am not objecting to revelation, all I'm saying is that natural boundary exists that should be observed.
***May be one can afford the absolute concept of God. But its impossible for every human being to afford the questions it brings, the philosophical problems it creates, the hurdles it builds up in the way of objective analysis (science), the prejudice it gives birth to and an inifinite no. of assumptions it demands to be made. It is very easy, indeed, to criticize human knowledge and its limitations. But very hard (if not impossible) to come with right and absolute solutions to human problems.***
The main issue is one of consistency. We want to be consistent in the methods that we accept. If philosophical justification is part of our scientific scheme, then we better darn well justify the boundary of the philosophical stance. We can't set unnatural boundaries for philosophy just because we like to use it here, but not there. That won't do. On the other hand, that doesn't mean that there aren't real boundaries to our understanding such as that prevent us from selecting a particular religious outlook. Religions generally claim that their doctrines are the result of revelation. Well, let them claim that and let religion continue uninterrupted, but the issue of the nature of an underlying order to the world is really a segregated issue from philosophical/scientific inquiry.
***Science, as we know it in a human sociey, is, of course, not the most objective method of studying existence. But, I feel it very comfortable and self-assuring that to assert here that SCIENCE IS THE MOST OBJECTIVE METHOD HUMANS ENJOY. ITS THE BEST WE HAVE.***
Science is the most objective of what? The best we can say is that science is the most objective discipline at developing models that match predicted observables. This doesn't tell us anything about the nature of those models. In order for those models to have any significant meaning they must be enriched by philosophy. The progress in philosophy is slower than science, but nonetheless it is a progressive discipline with high rewards. Science and philosophy are the tools to understand the order in the universe, and this necessarily involves a discussion of metaphysics.
Warm regards, Harv