Well I think "both" is the first alternative described: get rich any way you can, then use the money for real good. I think Bill's Microsoft was definitely not very interested in "Don't be evil" -- monopolistic practices, stealing ideas and technology from Apple (who often stole themselves), trying to kill free software (see: home brew computer club), etc.
Don't get me wrong. I have tremendous respect for Bill -- I look up to him and give him a LOT of credit for his recent work and humility. But I don't think Bill did "both". He definitely fell squarely into the first limited category: being a ruthless capitalist to get rich, and then trying to figure out how to actually bring some tangible good into the world with that money. (See also Andrew Carnegie)