I always stick with the 'good' choices. I can't help it, I just can't bring myself to hurt those poor widdle NPC:s. But there is a secondary reason to this: I always help people because I'm a sucker for side quests. I recently finished Mass Effect completing about 98% of all the missions the game

(Not including all the achievements, I just played through my first time.) Clocked around 40 hours.
However, I don't play strictly as lawful good. If the situation requires drastic measures, I'll do what it takes to finish the job. For example, by the time I finished Mass Effect my Paragon points were way over the scale but I had about two blocks worth of Renegade as well. I wasn't above sticking a gun to a gangster's face to avoid having to fight and kill him (which ironically would have made me the good guy for 'trying to talk sense into him' instead of taking the aggressive approach) and at one point I sacrificed the lives of two scientists to capture an alien terrorist who, if he had gotten away, might have blown up an entire planet. And as for situations where I can either help the guy for free or extort him for a 'helping fee', I'll usually choose the first option unless the prize is really worth it. Like a really rare item or LOTS of money. Usually the peasants are so poor they can't even offer me anything of value, so it would feel like taking their last possessions, and I couldn't do that!
Yeah, I'm really like that. Except for the helping everyone I can find for free.