zoey is not a lap dog as well. and she prefers to sleep on the floor than on my bed. the only time that she will sit on my lap is when we are in a car. she also insists on sitting on my lap only and not others.
as for the humping part, i think it is quite normal for male shih tzus as my i have 2 friends who owns male shih tzus and they started humping people's leg at quite a young age.