Max games: Yes, by position.
Max IP: Normally for your entire staff. Is to prevent people from drafting new starting pitchers every day and building up really high K and W totals.
How it should affect your draft: It means that there's more of a premium on quality players and less of a premium on utility guys since you can only have 162 games at 3rd base so it doesn't help you much to have 3 players who can play there because if you put in someone every day, you'll run out of games before the baseball season will. Not much of an effect, granted, but to the extent it is a consideration, that's it.