In my own experience I have discovered that if you kill a target instantly with a Paralyze poison on the arrow, they become Paralyzed even in death, can be alot of fun.
But how does using Paralyze with magic work? Possible to get the same out come and how?

For instance if I shot my enemy with Paralyzed arrow and the target didn't die but he was still paralyzed when I killed him with the second shot without poison on the arrow, he would not stay in the paralyzed 'form'.

are you talking about the biology behind it or just how magic would translate to paralysis?

arrows themselves can kill + paralysis poison and enemies are suspended in the form of death

however a paralysis spell just freezes the enemy, no damage is inflicted so to answer. No

Unless they fall at a high area.

well, I enchanted my daedric greatsword with paralysis and shock damage so when i kill something it freezes falls all stiff like, and once the spell effect wears off they go limp.

If you use Paralyze poison on a weapon and get a instant kill, they will be stiff all the time. It's crazy, you throw a stiff person over a cliff or just a little tower at some fort, the person will jump around crazy all over the world, spinning like a crazy spinning machine, just ridiculous.

what happens if you cast a destruction spell and paralyze at the same time at an enemy with almost zero health?
will they go limp after a while or stay paralyzed?

Yea, used the enchantment rather the poison, but i love that on a bow, those are perfect for when i go to wreak havoc in Markarth.

It says here that frost damage paralyzes targets if their health is low, then I wonder does one hit kill count? You hit with frost spell on a target that has 100% health and you get a instant kill, will he then be paralyzed or not? http://elderscrolls.wikia.com/wiki/Deep_Freeze Destruction 60, Augmented Frost Frost damage paralyzes targets if their health is low