if you mean for ex. a Muslim have a non Muslim friend whose celebrating his birthday and that Muslim is invited,so yes he can ithink
The better question is, why do Muslims not celebrate Christmas? This is because Christmas is a specifically Christian religious holiday - the original name of the celebration was Christ's Mass and then shortened over time to Christmas. In Christian religious beliefs, December 25 is the day that Jesus was born in Bethlehem to Mary and Joseph. Muslims believe that Jesus was a major prophet of Allah, but that he was completely mortal and not the Son of God as Christians believe. Basically, it makes no sense for Muslims to celebrate the birth of the Son of God because they don't believe Jesus was the Son of Allah. For a Muslim to celebrate Christmas, or at least the religious aspects of Christmas, would be for the Muslim to in effect be turning his/her back on the teaching of the prophet Muhammed (pbuh).
The Muslim skeleton and the non Muslim skeleton are the same ..Muslims are humans just like every other religion.
Yes. Even Islam-derived religions like Druze, Baha'i, and Sikhism do not celebrate Ramadan. If a person considers Ahmadis to be non-Muslims, then the answer changes to No since Ahmadis do observe Ramadan. However, there is much controversy over whether Ahmadis are or are not Muslims by different people.
respect their contracts and agreements with Muslims and not kill the Muslims
no it actually really isn't you see Muslims can adopt to civilization in non Muslim countries
Shaykhs were not involved in governing the non-Muslims because they were local Islamic religious leaders. Ra'is were the ones governing the non-Muslim families and non-Muslim religious leaders.
Non-Muslims inspired by other Muslims all over the world lead them to mosques !
Actually, most countries are non-muslim, meaning either that they don't have a muslim majority, or that they don't have a muslim government.
Indonesia has over 100 Muslims. In fact, nearly non-Muslim country has well over 100 Muslims.
There are certainly contexts given in the Qur'an for fighting holy wars (jihads) against Non-Muslims, usually those relate to (1) Non-Muslim groups who oppress Muslims, (2) Non-Muslim groups already in conflict with Muslims, or (3) Non-Muslim groups who do not permit Islam to spread in their lands. However, the Qur'an does not argue that all or most Non-Muslims should be violently targeted.
Yes, they can go to anyone's grave
Never Muslims neither tend nor required per religion to irritate non Muslims. Refer to the related questions listed below for more information on the Golden rules of Quran (the Muslim holy book) and how Muslims treat non Muslims.