Inboard or outboard?
rbh is correct except storms were left out of the equation. When the wind comes up on that huge lake which is bigger than most of the bays and sounds many of us "salt water" sailors ever see.
A outboard powered sailboat will hobby horse in big waves and the propeller will come out of the water. The faster you go however the better it is.
I have sailed on Ontario in a Grampian 26. It was ok.
Small boats with outboards are fine. Just keep in mind that Ontairo is not a lake, it''s a small ocean.