There is no need to convince anyone to go out and buy this game. The gaming God's simply demand it!
For an action adventure game it just doesn't get any better than this on the PS2. For starters, the graphics are stunningly good looking for a PS2 game especially compared to early games on the system. I happen to have a widescreen HDTV allowing me to take advantage of the game's widescreen 480p mode which makes the visuals significantly clearer and more detailed. Characters are detailed and have fluent animations all around. Many environments have shiny surfaces with reflections and advanced looking "bump mapping" and other effects you might think are only available in modern PC games or Xbox 360. Kratos' blades of chaos (your main weapon) swings in a brilliantly bright streak of fire as you whip the blades around attacking monsters. It never gets tiring to see those kinds of special effects from your weapons or magic since they look so good.
What makes God of War's gameplay AAA quality is the experience the developers show by making this game highly efficient in how the levels are designed and in how the amount of action and challenge is handled. This game is perfectly balanced in every way. Rather than scrambling through long boring levels fighting off waves of monsters, each area is sectioned off into seperate "battle zones" where you'll have a bunch of enemies spawn and then you have to figure out how to take them out as fast as possible. There is often some unique challenges thrown in each time such as having to kill certain enemies first to prevent re-spawns or taking out archers in the distance before killing a larger foe. You can often use the environments to your advantage as well and there are times when using certain moves work much better than just hacking away. There are many moves to learn in the game but they are all easy to perform and remember. This means combat never gets boring because it is easy to string together incredibly devastating combos or use powerful magic spells to get you out of trouble. You can even grab hold of guys and rip their bodies in half!
One of the more unique features of the game however is that during certain moments when attacking enemies you can pull off even more dramatic moves by tapping or pressing whatever button is displayed on the screen. If you are fast enough, this will make Kratos execute devastating finishing moves automatically. What I love about this so much is that it allows you to perform awesome moves that you normally couldn't do given the limitations of a console controller. For example, during one boss fight once he is stunned there is a "O" button symbol over its head. You press O then Kartos wraps his blades and chain around the boss's head, then you press X quickly and he jumps up on top of his head then press square and Kratos will jump in the air and then stab his blade into the top of the boss's head causing lots of gushing blood. Although God of War is a pretty hard game on default difficulty, it rarely gets frustrating becuase there are frequent saves and checkpoints just before every hard section so if you die you can start right back where you left off. The puzzle solving elements are pretty mild and appropriately spaced out. You can use simple logic to solve them and you probably won't get stuck for too long anyway. Most "puzzles" involve moving blocks of some kind around a room to open a door, defeating monsters a certain way or running through an obstacle in a limited amount of time. I also love how the story unfolds as you play. You start out without knowing hardly anything about Kratos or what the Greek Gods want from you but the story unfolds through pre-rendered and real-time cut-scenes. The level designs fit in and make perfect sense with how the story progresses and based on Greek mythology. There is also some foreshadowing of events to come later as you fight your way closer to your goal but I can't be specific without spoiling the plot. I can only say that this games does a great job of making you feel like you are playing a pivotal part in some ancient and epic Greek tale.
The music and sound effects are obviously terrific but I found the orchestral scores to be of such a high quality that they could easily be used in any feature film. The music is recycled a bit with different themes on just a few scores repeated often but it sounds so good that it hardly matters.
From start to finish, God of War is one hell of a ride. It is one of the most technically sound and developed games I have ever played and in my opinion, the best straight-up action game on the PS2.