Each RPG has a different set of classes, but I generally prefer the fighter types, mainly because they are relatively simple to play (usually), and they tend to deal more damage than other classes.
its very true that most warrior tend to do most dmg but the mage seems to be stronger than the ranger but then again the mage does take more mana so i prefer the ranger
depends on the genre of the game. if we're talking about medieval type rpg's i would always go for the warrior as i don't really like to think about combat that much. however in games such as fallout (where there is a major amount + guns) i would always go for the ranged type combat or the shotgun. i am the type to snipe at a distant, then switch to mid range then shottie.
i always choose the magical class. usually the attack mages but sometimes the healing mages. NEVER the balanced mages.... i really dislike those. they are nice for the begining of the game but towards the end they are much weaker then the other classes.
I choose the most adapatable class. Usually that's the ranger/rogue type classes, which often has abilities like finding more money, uses a variety of weapons, has healing skills and stealthy skills.
It really depends on what class the game has I would go for rogue because in most games rogue get invisibility and others which helps you survive through the game.
I usually go with the Speedy Sword user class. They usually have the most bad-*** back story and designs though I would say know to mythical creatures.