Hi,
I noticed this question has been raised several times, but I didn’t find any satisfying answers. I have objects that have rigidbodies and want to attach them to my character which also has a rigidbody. However, when attaching them to its hand, the object does not follow well. If setting isKinematic=true, the character gets totally crazy, it’s fun but undesired 
I could remove the rigidbody with Destroy, but then I will lose all its parameters which are required when detaching the object later on. Is there any solution to remember the rigidbody apart storing its parameters in an ad-hoc structure ?
I believe that isKinematic = true would disable the physics for the attached component, but presumably that attached component has some colliders? They will start affecting the rigidbody of the thing to which they are attached. You would probably want to disable all of them too. Loop over GetComponentsInChildren(Collider) and set the enabled to false.