The Mass Effect series is sooooorrta open world? It's really good and like the entire trilogy is like 20$ on amazon either today or soon, thats a steal, the first one is slow and gross, but 2 and 3 are really fucking good even if the ending isnt so good its worth playing, there's going to be a 4th, the multiplayer on 3 is actually really good and i think bioware is going to flesh it out even more with #4.
Fallout 1 & 2 are good, they're kinda slow though, you can play it one handed if that means anything.
LA Noire is pretty good.
if u like arpgs like diablo play path of exile
mass effect is good