“My film centers around a couple of fast food joints like Mcdonald’s and Burger King and it’s a major theme in the film with their names and logos are often mentioned. Is this okay or do I have to blur these out because of trademark laws?”
You should ask for permission to use ant trademark in your film. There is no fair dealing for trademark. Fair dealing is the copying of a substantial part of any protected material for one of only five limited purposes, research or private study, criticism, review, or news reporting. Thus, all trademarks must be cleared, no matter what the use; except, of course, if you can make a case that the use does not violate the trademark act (i.e. not a passing off, and not a defamation of the brand). [For more information on the infringement of trademarks see: Trade-marks Act of Canada, Section 20 and Section 22 http://laws-lois.justice.gc.ca/eng/acts/T-13/page-8.html#docCont]
To check if something is trademarked or not in Canada: http://www.ic.gc.ca/eic/site/cipointernet-internetopic.nsf/eng/h_wr00002.html