gifts from mothers do you tell the tax man

Hi there,
my mother made an investment and it paid off, she is 84, and we filled in her self assessment tax returns for the 3 years the investment payed off, and she paid her taxs to the Government. She now has bought me a car, as I was the one who talked her into the investment, its for me, my mother and father, really, but as she bought the car from her bank, its her car, how do I say its my car ??? As she has bought it, does she just say to me here is your car ??? As I have to say whose car it is on getting the insurance. Also, do we have to tell the tax man we have bought a car, and its a gift for me, I say for me, as the car will be drove by me 60% and my father 40% We have a small business, but do not earn much and I am no tax credits, thus do I tell the tax man I had a gift of a car ??? If money I would think maybe, but a car ???

Wayne