Give £5m to my closest family, i.e £1m each.
Buy a mansion with pools, cinema rooms, games rooms etc. If I won more I love the idea of buying an entire street out for all my family/friends to live on that you could make private.
If I was still in education, I'd more than likely pull out, unless I was really that interested or close to finishing. If not, then unless I could get a job I really liked, I'd probably work for a half a year or so then retire early. Would only start working again if I ever got bored...but with that amount of money, I couldn't imagine it. It's like a dream
Oh, and maybe a couple of grand to charity, just to show I'm not a heartless ****.