Preferably just the whole cock. Very rarely do I want my testicles played with. And if I do I let the wife know.

Hold them gently, but that's about it for me

And don't suck them. That just hurts

I love when she plays with it while sucking, wether it be light strokes or even licking it to. But I prefer when her hand adventures even farther towards my perineum and anus

I like getting my balls fondled & sucked. There's just something hot about a woman taking care of the parts of her man that will breed her.