the first stalker game is pretty awful. try Call of Pripyat if you have the chance, it's a lot better.
then there's Dead Island, which can be entertaining for a while.
as for Arma 3... it's complicated. as usual with Arma games there is no game to speak of. a bunch of missions to give you a taste of what Arma is like and a single-player campaign that's broken up into episodes (read: separate missions) - not very sandboxy. the closest you can get to a sandbox in vanilla Arma 3 is the two Escape missions. you're dropped in the middle of nowhere on one of two islands and have to escape from it, avoiding enemy patrols. but they're not long enough to justify buying the game.
if you really want to give Arma 3 a chance you could try its RPG modes made by modders. I never play those because I don't find it fun playing cops and robbers in a world that has no civilians (huge empty areas, huge empty towns, it's just depressing).
you'd be better off waiting for DayZ to come out. at least in that game towns and villages have zombies