Metro 2033 is often used as a benchmark game. In truth, the game does not appeal, probably due to poorly written game engine. Other games like Rage look much better and do not tax the system as much. A big hype for nothing.
One of the reasons for the extra power of graphics processing power is the requirement to draw volumetric fog and smoke effect. Other than that, the game looks OK at best, it does not stand out.
That being said, the game does impress with the level of detail. Character models are well fleshed out. The atmosphere and environment details are also done extremely well.
In the world of Metro 2033, you face zombie mutants from some unknown origin. They are fast, somewhat. They leap, jump, and sprial towards you like a brainless monster.
The sound effects is mediocre, though it is designed to be creepy and eerie. The game opens in a world that feels like the World War 2 era, except you have some advanced weapons from the post 1990s. The wierd combination is a confusion much not needed.
Supposingly, the graphics is what drives the popularity of the game, as with most current day games. Long gone are the traditional run and gun styled first person shooters.
The game developers incorporated many realistic elements into the game. Looking through your goggles is more difficult. Also, breathing without your mask makes your vision more blurry. This is a neat feature, though not the first to be used.
Playing Metro 2033 is probably a good idea but keep in mind, there are better looking games out there.