What is the definition of gheebah and what is the ruling on it?

I am a young Muslim man who believes in Allah and His Messengers and His Books, praise be to Allah. But sometimes I feel too lazy to pray. I am looking for a solution and a way to make me not be so lazy. Please note that this is what I want but the tricks of the Shaytaan are too strong.

What is the Islamic ruling on the issue of imitating the kuffaar in their customs and dealings? What are the guidelines concerning that in Islamic sharee'ah? Is every imitation of the actions of the kuffaar regarded as a haraam kind of imitation, knowing that there are many things that the kaafirs do that are not haraam and are not condemned by sharee'ah, where the one who does them does not do them merely to imitate the kuffaar, but because he thinks those things are good, as Ibn Mas'ood (may Allah be pleased with him) said: "What the Muslims think is good is good before Allah"?  
Please advise us, may Allah honour you, and please give me a detailed answer and explain to me the guidelines on this matter.

could you please advise us about how improve our manners, and raise our children to have good manners? As many of the scholars mentioned, they studied under their teachers for years to learn proper manners. I am very concerned because it seems that we are surrounded by bad examples and role models, and the standards of society are very low. I am a revert to Islam so I was not raised with good Islamic manners. I don't have the knowledge or training to be a very good role model. My childrens TV watching is very restricted, but they still interact with cousins and friends who pick up bad words and attitudes from TV. We also educate our children at home. But as much as we shelter them and instruct them, they seem to pick up some of the attitudes of the greater society. I am torn between whether I should continue trying to remain patient and remind them gently, or I should become more strict to enforce better behavior. We would really appreciate any advice that you could offer.

Firstly: I apologize for asking such a question, and so that there will be no room for doubt about my intention I will say that I bear witness that there is no god but Allaah and that Muhammad is the Messenger of Allah, and I am completely content with Allah as my Lord, Islam as my religion and Muhammad (peace and blessings of Allah be upon him) as my Prophet.   

I am asking about the Sunnah, because there are many reports of a single hadith. For example, we may find in Saheeh al-Bukhaari a hadith that appears in a form different than that in which it appears in Saheeh Muslim. Why isn't the Sunnah like the Holy Qur'aan? What is the difference between the Sunnah and the Holy Qur'aan? Is the Sunnah part of the Wahy that was revealed to the Messenger (peace and blessings of Allah be upon him) or is it just his words and deeds? Is it one of the characteristics of Prophethood or what?

Is it true that anyone who does not accept that kuffaar are kuffaar is a kaafir himself, even if he prays, believes in the Qur'aan, and the Prophet Muhammad? If so, what is the proof for this? Can a person insist on believing that Jews and Christians can be believers and go to heaven after being shown clear evidence against this, and still be considered a Muslim?

Is it permissible to give charity to non-Muslims if they are in urgent need? Will the person who gives such charity be rewarded?

My neighbour is an American Christian, and she and her family brought me a gift when it was Christmas. I could not refuse the gift, lest she be offended.  
Can I accept this gift, as the Messenger (peace and blessings of Allaah be upon him) accepted gifts from kaafirs?

A non-Muslim friend of mine asked how I could prove the existence of God and why He has given us life, and what its purpose is?
My answer did not satisfy him, please tell me what I should tell him?

Can you give us an idea about the Dajjaal, Al-Daabbah and Ya’jooj and Ma’jooj?

What is customary is for us to say “Blessings and peace of Allah be upon him (sall Allahu ‘alayhi wa sallam)” specifically for our Prophet Muhammad (blessings and peace of Allah be upon him); is it permissible to offer this supplication with this wording for other Prophets? Who are the only ones for whom the following phrases are to be used: may Allah be pleased with him (radiya Allahu ‘anhu), may Allah have mercy on him (rahimahu Allah), may Allah keep him safe (sallamahu Allah)? Is it permissible to offer supplication for a great scholar who strove all his life to call people to Allah and His Messenger, such as Shaykh ‘Abd al-‘Azeez ibn Baaz and other, similar contemporary scholars, when they die, by saying “may Allah be pleased with him” or “peace be upon him”?