Re: considering arabic culture to be part of Islam
I think the issue is fairly clear. There are things which are a part of Islam because the Prohpet(saws) commanded us to follow them. There are other things which people do even though we haven't been commanded. Then, it depends on the intention of the doer, if he is imitating the Prophet(saws) out of love, then it is considered "sawab-worthy".
It would be better if you could outline something more specific. I doubt people consider the chequered headgear to be a part of Islam. The ruling on daff though isn't cultural. What else? I cant think of many examples where arabic culture would be called a part of Islam..