Ethereum blockchain is a 2nd generation of blockchain which you can use to create decentralize application on top of it. It can handle simple programs rather than transactions only of who paid whom, how much, etcetera.
Ether is the native of of Ethereum blockchain which used to pay whatever you do on it.
It is a better blockchain, of course, compare to first generation blockchain - Bitcoin, which can only store transaction data.
It's planning to shift from proof of work to proof of stake consensus algorithm, which is a plus for me because you can save energy from it. The downside is that rich is getting richer because you can be the one who can propose a block if you have a huge amount of stake on the blockchain.