I think to sum this all up...."good grades" means grades eligible to get you into the college you want to be at?
For example, if the schools' webpage says minimum unweighted GPA of 3.0, that would apply for athletes as well, so don't even bother looking there unless your kid has an unweighted GPA of 3.0.
So, follow up question:
If you are dealing with the 0-4 scale, F's being a 0 and 4 being an A. And you aren't taking into account up-scores for honors or AP classes, what is a "good grades" GPA to you? I'd like to know so if a coach asks me "does your son have good grades" I want to know what my response should be, or should it always just be the unweighted GPA?.