Save the money for sure. In EUrope, you can live for free really easily, and you wont learn how with that kind of money laying around. It's good to have a little emergency stash though, in the case that something goes wrong. Find yourself a decent squat in London until you turn 18, try to learn the ropes of free living there. Once your 18, if London isn't your thing, get out on the road and find something nice. DONT SPEND THAT MONEY!! Seriously, unless you absolutely need to, or are totally sure on what you want, you can really quickly piddle away 1200p on beers, food, and useless crap.
If you really want to spend it, figure out on what. A vehicle is a decent option, you can live in it, and haul scrap or other things with it, to make your money back. 100 cases of beer is a better option. You can make a hell of a lot of friends. For a few days. Until your beer runs out.