Really liked one of the previous "dream team" answers, but of past Leafs only, I'l say I loved the high skill but coupled with extreme physical fortitude, will to win, willing to do anything it took to get that puck or score that goal or stop that rush. I don't need tough fighters, just tough players with a will to win that you can see written all over their face.
In goal, Curtis Joseph. Eddie Belfour. Felix Potvin.
At D, Dmitri Yushkevich is all I can think of.
At forward in my top 6 - Gilmour, Sundin, Clarke, Roberts, Andreychuk.
At forward in my bottom 6 - Tucker, Komarov, Santorelli, I'm sure there are more.
Grit with some skill, but most important - will to win, that shows up on the ice.