Private hours flown in aircraft below a certain weight (dont know what, but higher than most light aircraft!) dont count towards any flighttime limitations. You can do what you like.
As for instruction, I dont know for sure as Ive never been an instructor, but fairly sure that doesnt count either- I know several part time instructors, who's airlines have no interest in the hours they do, thus it obviously doesnt count in FTLs.
I think even things like joy rides etc in small light aircraft dont count either.
It does count though if someone pays you to fly them around in their King Air etc