Why do you need to invest them? You can just hold those 2 Bitcoins and that is an investment. You will probably be wealthy in about 10 years if you just hold them. Anywhere you put them besides and offline wallet and you are risking losing them. Don’t trust exchanges with much of what you have. If you get into trading, just use a small amount of your Bitcoins. You could diversify a little by buying some altcoins, but I still suggest that you keep them in a wallet where you control the private keys.