First I'm going to assume that you already know how to start the game up, so I'm not going to pull a BlueHighwind on you.
Now the basic controls are as follows:
Use the Directional buttons to move around, start can be used to skip cutscenes (and enter first person mode), select zooms in and out and the L1 and R1 buttons are to rotate the camera. That about covers the basic controls.
If you've played Final Fantasy Tactics you're going to recognise this battle system as this game was made by nearly the exact same people (yes!). Pressing Circle will open up a wire frame battle sphere. Anything inside this sphere is close enough to attack, cast spells, use items, etc. When an enemy is in range you can choose from a list of body parts to maul:
Head which affects magic. Neck (Only certain enemies). Chest (Again only certain enemies). Body which affects, something I don't know. Abdomen (only certain enemies, usually the weak point on their body) Left, Right or just plain legs which affects movement (Deal enough damage and you'll see the "move-50%" message. Left arm affects shielding I think. Right arm affects how much damage you do. Tail (Only certain enemies) Wings also affect movement for certain enemies.
That's it for combat. Oh no, wait different weapons. Different weapons do different types of damage. Clubs and maces do Blunt Axes and swords do Edged damage and Spears and crossbows do piercing damage. There are some exceptions to the rule but it generally goes like this.
Damn I have a bad memory. I forgot about Break Arts. Don't use them. They damage you and do bugger all to enemies.