I'd have to say Ovechkin is pretty much a total game-breaker.
His hat-trick the other night single-handedly sunk my Ducks....and that Phoenix goal, while partially lucky, was AMAZING
The thing is, he basically plays with zero Caps support. He also plays physical and hits like a train, something very rare with scorers of his talent level.
I do think, in two years he will still be way ahead of Crosby. Although Crosby will probably be better than he is so far this year then, Ovechkin will also have more NHL experience in the same way.
As far as Phaneuf goes, defence does count, but I'd take Ovechkin over Phaneuf any day of the week. It'd be fun to see though, out of 10 tries, how many times Ovechkin would beat Phaneuf one-on-one.
As for Ovechkin doing worse if he had better players with him, I really doubt that. With other threats, it would give him more space as well taking away some of the double-teaming on him (or leaving someone else open for the pass then).