I would stick with the first one.
In Bioshcok 2 YOU are the fearred one. You are a big daddy. Your little sister has been in a way kidnaped, and you will do anything to repond that love.
So the gameplay in Bioshock is pretty much the same as the gameplay in the first Bioshock. The one thing I missed is how cool your hand looked when you used the plasmids. If you havent played the first one, plasmids are something you use to do amazing things like shoot lightning out of your finger tips. Insted in the second one, you wear a glove so you don't feel more like the feared one. When you play Bioshock 2 your enemies are scared but that wont stop them from getting atom. Their are maybe a few enemies that might scare you like the big sister. Bioshock introuduce new weapons to keep gameplay fresh. One of the weapons you will use a lot is the big drill that big daddy's have. It does have fuel so you cant go around drilling evreything you see. But even when you do run out of fuel you can still use it to hit your enemies. And after you run out of ammo for all you weapons which probably will happen it will come in handy. Its a good thing you can loot from pretty much anything. Other things i did not like about the second one is you kinda feel very heavy so you move very slow. And i do agree with the video review that some places feel too familiar.
Graphics in this game are amazing. with the nice running water to the gorry halls you go through.
In Bioshock 2 their is great online play. If you don't like online games where it takes 30 seconds to reaspon you will like Bioshcok 2. After you die it takes about 5 or 6 seconds to reaspon. They have great game modes and nice online compotition.
Bioshcok