Greetings, Eddie, and welcome to the forum.
All praise be to Allah that your heart is warming to Islam. Only you can judge whether you need to hide your reversion from your family, but don't let the fear of their reaction stop you from embracing Islam once you've recognised it as the truth.
Perhaps your relatives won't be happy because they don't know what Islam actually is. Some people have negative views about Islam without really knowing what it's all about. Also people can be very set in their ways. You need to reassure them that you haven't gone off the wall. Here are some points that might be worth mentioning to them:
Islam is the only non-Christian religion which makes it an article of faith to believe in the central figure of Christianity, i.e. Jesus Christ (peace be upon him). If a person calls himself a Muslim and doesn't believe in, respect, or love Jesus (peace be upon him) then he is NOT a Muslim. No other non-Christian faith has this stipulation.
We believe that Jesus (peace be upon him) was one of the mightiest messengers of God, and that his mother Mary (peace be upon her) was one of the most pious and noble ladies to ever walk the face of this earth.
We believe that he was the messiah, translated as christ.
We believe he was born miraculously without any male intervention, which many modern day Christians today do not believe.
We believe that he gave life to the dead with Gods permission.
We believe he healed those born blind and lepers with Gods permission
However we do not believe that Jesus (peace be upon him) ever claimed divinity, or that he was God, son of God, or that he said "Worship me". Nor do we believe that he himself ate, or allowed the eating of pork. We also do not believe that he was crucified, nor died for anyones' sins. In Islam, each person is accountable for their sins, and each baby is born sinless. God is Just, and it is not in the nature of a Just and Fair God to make one person die for the sins of all humanity. It also denigrates the power of God that he could not forgive mankind without making a sacrifice.
We believe in One God, who has no associates whatsoever in His Divinity, and we believe in all the prophets that He sent to mankind, whether we have heard of them or not. That includes the final Prophet Muhammad (peace be upon him). We are not allowed to pick and choose those we believe in. They didn't preach different faiths, but said to people "Worship Allah, my Lord and your Lord, and associate none in His Divinity." We do not reject any of the prophets (peace be upon them), neither do we exaggerate the status of any of them to something it wasn't (i.e. divine).
We also believe in the existence of all the books of God i.e. Bible, Torah, Psalms of David (peace be upon him), and any other books that we have not been told about, revealed before our time. We also believe in the angels, and Day of Judgement.
All the Messengers of God preached the same message, which was to worship ONE God. The message didn't suddenly change when it came to Jesus (peace be upon him) with a three in one god. Jesus (peace be upon him) preached the same message that Moses (peace be upon him) had preached earlier:
'Hear, O Israel, the Lord our God, the Lord is one." Prophet Muhammad (peace be upon him), Jesus's brother in Prophethood, and the last of the Prophets, came preaching exactly the same thing. Thus by becoming a Muslim you are following Jesus's original message, i.e. what he actually preached. As a Muslim, you love, respect and honour him more than you did when you were Christian.
God is One, with no sons or daughters or relatives of any kind. He is not similar to humans in any way, and He is Eternal and never dies. He is the only One that can answer prayer, no human being who has died, has any power to help us, we pray to God only. The Qur'an is 100% God's word, unlike the Bible.
I found the following excellent link which gives commands that are common between the Qur'an and the Bible (such as abstaining from pork, alcohol, women covering themselves, prayers and washing before prayer, Jesus peace be upon him not being divine etc etc), which Muslims follow and Christians don't, and it gives you all the Biblical (and Qur'anic) references to back it up.
http://www.irf.net/index.php?option=com_content&view=article&id=128&I temid=146"]http://www.irf.net/index.php?option=com_content&view=article&id=128&I temid=146"]http://www.irf.net/index.php?option=com_content&view=article&id=128&I temid=146
Various issues are discussed and then the conclusion is reached that, actually, Muslims are more Christian than the Christians themselves! All because they are following the unadulterated teachings of Christ (peace be upon him). But it's explained in a nice, non-condescending and non-patronising way.
This may be useful when it comes to telling your family.
Peace.