Ah, Platoon. I remember it well. Ocean's game of the movie was well-received on its first release in 1988 for its atmospheric feel and tough, varied gameplay, and those qualities still stand it in good stead today.
The graphics and sound are perhaps a little basic by current standards, but there's plenty of gameplay in here, from the arcade-adventure and mapping of the early levels to the 3D maze Operation Wolf-clone sections later on. There's a real tension to the game, and you find yourself jumping at the slightest sound. It's very playable, though, and the sectionalised format makes it addictive, as each section is just short enough that you always feel you'll complete it (next time), but hard enough that you rarely do.