Both of these offer different advantages:
Bitcoin is the safest cryptocurrency and has reached the widest audience.
Not to mention holding a third of the entire market's value.
Ethereum is right there with it, holding second place on the ranks.
DApps, DAOs, and Smart Contracts changed the game.
So where do you bet your chips?
BTC or ETH?
Definitely with bitcoin, but from an investment point of view, I think both can go hand in hand and may offer equal chances of high profits in a long term investment plan.
I think both of these are here to stay and grow, so none of these is actually a bad bet.