I don’t think it brings you happiness, I think you have to be happy already but I do think so many many people would be happier without all of life’s pressures, which a lot of the time come down to money so of course a huge win would be the cure to all that. No more burden of bills, housing costs, childcare costs, travel costs etc
I think many people would be happy with the life they have if they just had enough to live a nice little life, cover their bills comfortably with a few treats, be able to take their family on holiday, be able to afford to spend time as a family rather that ships in the night tag-teaming to their jobs etc
I remember when we got slightly better off, it was just so nice to be able to go out for a meal as a family without having to choose between eating out or paying our gas bill.
I grew up in poverty and it was tough but we were happy. Dh and I have struggled with money throughout our life together but we’ve always been happy together.
Winning such an amount would be unfathomable wouldn’t it? I would get such a buzz through helping out my closest family and friends. I wouldn’t be able to start buying ridiculous things though because of how I grew up, I’d obviously treat myself but could never justify spending say 5 grand on one piece of clothing, I just find that vulgar when other people can’t afford to eat.
I’d want to get a house in the middle of nowhere, be quiet and spend real quality time with my family. I’d also really love to travel and show my children the world.
I think I’d probably be a bit of a rubbish lottery winner as I wouldn’t suddenly be going out to buy a Lamborghini or something 
I do have a list of people though who have helped us out throughout our lives at times when we’ve really needed it and they will be gifted with a lump sum if we ever won. They probably wouldn’t even realise how much their small actions meant to us.