The first thing that sticks out like a sore thumb is the music...there isn't any, during the gameplay anyway. Be prepared to just hear gunshots. All you get for music is the music on the title screen, which after getting a game over in which you are returned to the title screen, it won't play it again. Other than that, the level end screen which totals up your points has music, but that's it. It's not even great music, it's just average, so musically, this game fails.
Aside from that major letdown, the game is awesome. It's so satisfying to blast away at enemy terminators, racking up tons of points. There's four levels, each going along with the movie (which I haven't seen yet), and at the end of each level there's a boss, each with a different strategy to beat it. It's a lot of fun.
I picked up T2 The Arcade Game for a mere $1.99 at a used game store, and it was worth it. I highly recommend you try this game, wether it be through an emulator or a physical cart (which is the best way to play a Gameboy game in my opinion), give T2 The Arcade Game a try.