Thanks for your question. This is Michael from DynamicLegalForms.com. The answer, I guess, would depend on the context of your question. What specifically are you thinking about?
Normally, your Will dictates what happens to your property when you die. In Ontario, your spouse can make an election: take what they are entitled to under the Will or take what they are entitled to under matrimonial laws. Now, if there is a marriage contract in place, then the choice would be: take what you are entitled to under the Will or take what you are entitled to under the Marriage Contract. Finally, a Marriage Contract does not say who gets your property when you die. It only deals with support, division and ownership of property during / after the marriage, etc. But it's not a way of distributing your assets when you die.
Hope this helps!
Jan 3, 2013