While Bitcoin is just a cryptocurrency, Ethereum is a broader ledger technology used to construct applications. Ether is the principle cryptocurrency of Ethereum, but generally you’ll just see this referred to as ‘Ethereum’ online.
Ethereum casino deposits essentially operate in the same way as Bitcoin deposits. You purchase ETH on a crypto exchange and then fund your casino account using your crypto wallet.
The choice to invest in Bitcoin and Ethereum is largely a personal one: both ETH and BTC are excellent deposit options for Australian gambling sites.