Could you relate Bioshock to any other game?
Yeah. Imagine Half-life's gun system combined with more open levels, the magical powers of Oblivion, and 1959. I've never played System Shock.
Both Bioshocks are great, but they are very short. The story, you won't understand it in 2 unless you play 1 though. Interesting ideas they had. An underwater city where people were free to invent or achieve as much as they could. Nice.
2 improves in gameplay, but is shorter and the story is less surprising.
With one trigger/button, you wield plasmids. With the other, guns. Of course, in Bioshock 1 you wield one at a time...
Bioshock 2 got bad reviews for being like Bioshock 1("It's feels like the same Rapture".../facepalm) for whatever reason. There is money, but you only buy plasmids, ammo, and Gene tonics(buffs) with it.
The hacking minigame gets annoying, but like most of the gameplay, it was improved in Bioshock 2. Some of the best parts are the Big Daddy fights. They're like giants wearing diving suits with drills or guns. They're hard to kill, but you get to the ADAM, currency for Plasmids and Tonics.
Overall, yes. Gameplay is fine, story is original/surprising, and they'll give you a week of things to do.