When charging ipad is it normal that ipad sort of vibrates slightly?

This is normal, and harmless. Many types of AC/DC converters allow AC onto the frame of the device. Although it feels odd, it is quite harmless because it cannot source enough current to harm you.

I have the same problem with my iPhone 5 when I'm charging it gives me an electric shocks on its back , it didn't happened to me before, so I'm very worried about my iPhone .. should it hurts the battery life or the iphone itself ????

Unlike the iPad charger, the one that the iPhone comes with doesn't seem to let high amounts of AC onto the shell of the dock connector (and device body).

If you're feeling a tingle on your iPhone while charging, are you using an official Apple iPhone charger, an iPad charger, or some 3rd party charger (with your dock cable)?

Yes I'm using an official charger , but I don't know how to fix this problem , now I'm charging it on the computer or on the PS3 ,and I don't feel any tingle on the iPhone ..

None of my iPhone chargers behave like my iPad charger, likely because the iPhone charger is a switch-mode design that completely isolates AC input from DC output. So if you're feeling a tingle on your iPhone when using a standard-issue iPhone charger, then it could be defective. Do you have friends with iPhones such that you could borrow their charger to see if it behaves the same? If another's charger doesn't cause this, then replace yours just to make sure its not a safety issue.

Note that the USB port on your computer and PS3 are completely isolated from their AC input, so that's why you won't feel this when charging with those devices.

Yes I will borrow a charger to see if it behaves the same .

Is it okay to charge my iPhone on a Laptop or PS3 until I find a solution for the charger ?

Yes, though it may take a bit longer to charge since these devices may be limited in their current output.