Gretzky also played in an era that doesnt have nearly the protective equipment, nutritional knowledge, and injury treatment that Ovechkin has at his disposal. Two different eras, so please dont compare what one would have done during the others time.
Keep in mind Gretzky was a passer FIRST, shooter second. If the Great One had the same scoring mentality that Ovechkin does, which is shoot shoot shoot, he could have had 1200 goals.
I personally dont see Ovechkin sticking around long enough to touch Gretzky's record. and asking for 40 goals when your 35-40 is A LOT. I think the record is safe.