Re: What happens to my two Bitcoins (just for example) if I lose my security key?
Today about 17,000,000 (17 million) Bitcoins are in existence.
Today over 18,179,788 BTC Circulationuntil such time that someone had invented a machine that can decode public key and get the private key of that address.
Impossible, before that machine launching, Bitcoin system has upgraded better than now.I like it how from the very beginning you inform us that you have two Bitcoins 
OP's opinion example only. don't take it to your Brain.you must ready for lost all your bitcoin, need to back up and save your private key with several document because when you lost at the first document saving you still back up with other document.
I won't like your mind. Investing must ready to get profit, not get lost.How much document for backup? 2? better to back up on empty paper or plate steel.