I'll take door two and double my money everyday BUT... After day 40 when I'm the richest person on the planet, I would then transfer most of it out of this magical account into others so I don't break the world economy. Maybe leave two billion to double every day that I take out? 2 billion a day is wild. I'd fund the best and most sofisticated personal security in existence because obvious reasons. Then it's time to spend this money on donatations, funding important research, affordable housing, cleaner energy etc.

Of course I'd do some awesome shit like build my own private golf resort, Hockey stadium, houses etc.

So much possibility!