Dad, if you've won the lottery - then make sure you pay for my house.
Naturally if it's me that's won the lottery, then once I've given mummy and daddy about £300, then I'd go out and buy:
Everyday road use: Aston Martin DB9 or the old Square Vantage
Fun for the weekend: Ferrari 250 GTO SWB, Probably an Enzo as well and that weird thing that Jason Plato set light to, and JC managed to break - oh and a team of engineers in a van following behind me.
I'd also buy a double decker bus, strip the top deck out, and put 4-5 beds and a shower in place, strip the bottom out, and plumb a bar, complete with beer on tap, and multiple plasma's with satellite TV.
I'd probably buy 5 of those, and rent them out to you lot!