@BTCSports,
Since I think you know a lot more about how betting works than I do,  I would like your input on how to structure the bet.

I am saying that Bitcoin will outperform ALL of them.

How I imagine it would work is if the current (easy math) price of each is:
Bitcoin is $10.
Silver is $50
Gold is $1500
Dow Jones 10,000 points
Nasdaq 2,000 points
USD is $1

in two years if everything doubles (except the USD will still be worth $1USD) to:

Silver is $100
Gold is $300
Dow Jones 20,000 points
Nasdaq 4,000 points

Bitcoins would need to be more than 100x more  ($1,000 a coin)  for me to win the bet.

Please let me know if anything is not clear,  or you think I am missing something.