Blackjack has the lowest house edge of any game in the casino. Next to it are games like: Video Poker and Pai Gow Poker, Craps and Baccarat.
Avoid games like Keno (usually more than 25% house edge) Slot Machines (HE could be even 15%). Roulette is not that great etither.
Assuming you play optimal strategy and the rules are good for you (dealer stays on soft 17, BJ pays 3/2, 6 deck show max), etc.
I find craps played optimally is your best game odds wise. But if you lay high max odds (which is super optimal) variance can make you rich or decimate your roll. And don't be throwing around tips like ad drunken sailor when you win either. B/c it goes both ways and they don't tip you when you lose.