The hand (top left corner) is which hand is dominant. If you hold a weapon in your left hand, you'll get higher attack with it than if it were in your right hand. If you hold a shield, blah blah, you get the point.

Attack, as well as defense and magic defense, are your base stats. Just like as in every other game. The percentages are as follows: Chance to hit, chance to block physical, chance to block magic (block may be dodge.. I'm not positive).

You can also assume that the 2x, 1x, and 0x modifiers do what you expect them to do, because... well, they do.

What is it they say about silence being golden?