All of exchanges that i am using, closed their bitcoin wallet for deposit and withdrawal. Some of them want to take my BTC and give me BCC instead. This is certainty and they said on news.
BCC's value is 0.1 BTC at now.
What should i do for holding value of my BTCs in dollars?
Some of them hasn't any option for trading BTC/USD.
Should I exchange my BTC with ETH?
That's a terrible mistake leaving your bitcoins with exchanges, they can come and give you any story tomorrow about how they lost your bitcoins and that's nothing you can do, it's advisable to always store them in preferably an offline wallet.