you don't need a game, you can get similar results just by creating you own fantasy portfolio on loads of places online.
www.fool.com and Yahoo Finance used to have something like it.
Those places are also good places to learn the ropes and principles.
Never play the stock market with money you can't afford to lose.
Only the pros tend to play with FOREX, and even then it usually isn't their own money. Unless George Soros is your mentor, I'd say that you have no business worrying about FOREX until you have a very good handle on the more basic stocks and other investment vehicles such as bonds, unit trusts and so on. Hedging would be another useful mechanism to understand.