I am trying desperately to find information about my maternal grandfather. His name was Robert Spence. His death occurred somewhere between 1945 and 1955. What route should I take to obtain the information I require.

You can request a death records search from Service Ontario and use the result to order a death certificate.  Anyone can apply for a short form death certificate but next-of-kin (proof required) can request a long form which will be certified and include more information.