What is Buddhism? I suggest reading Steve Hagen's book: "Buddhism Plain and Simple" if you really want to know. Strangely it seems that the more I internalise buddhism's teachings, the less able I am to describe it. Here is an article in which I describe it.

For me, Buddhism is about having faith in the self, yourself, even though we can barely say that such a thing even has an existence.

It's about knowing that when everything you thought you knew is seen to be false, the centre of your consciousness and feelings is that which you must believe in blindly.

Buddhism suggests that happiness can be achieved through acceptance of the the world and everything that happens to us.
This appears to many people to be a flaw in the theory because acceptance can lead to inaction and in our everyday speech, people often consider acceptence to be coupled with a sense of finallity, apathy or even hopelessness.

I think that this is not a problem with Buddhism itself but rather a problem that Buddhism presents.

How do you accept something without submitting and resigning yourself to it? How do you fully accept something bad but still retain the will to do something about it?

For me, acceptance in the buddhist sense means "to be fully aware of your situation, being aware of what potential power of influence you have over that situation and being ok with it, whatever it might be".

It's possible to want to be somewhere without lamenting where you are.