Oct 23 (Reuters) - The following are the top stories from selected Canadian newspapers. Reuters has not verified these stories and does not vouch for their accuracy.
* Dalton McGuinty won't be challenging Justin Trudeau for the federal Liberal leadership. The Ontario premier has decided to look for challenges outside politics altogether.
McGuinty has been under mounting pressure to run for the federal party's top job since he shocked the nation last week by announcing his intention to resign as premier.
* A national index of well being, to be released Tuesday, shows that growing economic output since the recession has not translated into a better quality of life for many Canadians.
Reports in the business section:
* The federal government's surprise move to block the takeover of Progress Energy Resources Corp is adding to growing concerns about a "Canadian discount" that weighs on share prices and frustrates companies' ability to raise capital and do deals.
The government's decision immediately reminded investors of previous high-profile deals in Canada that fell apart amid government or regulatory scrutiny, and has created uncertainty about the bid for Calgary's Nexen Inc by China's CNOOC Ltd.
* TransCanada Corp said on Monday it had restarted its major oil pipeline to the central United States from Canada following a five-day outage to check for a potential defect on the line in the U.S. Midwest.
* U.S. President Barack Obama repeatedly attacked Republican challenger Mitt Romney on foreign policy on Monday in their third and final debate in an effort to blunt his opponent's surge in the polls with two weeks left until election day.
* Despite accusations that they are "killers of the sick and elderly," a growing number of British Columbia healthcare workers are resisting a mandatory flu shot, arguing that it is an issue of personal choice.
* Several reports stated that Royal Bank of Canada is on the verge of a deal to acquire the Canadian operations of Ally Financial Inc, the former auto finance arm of General Motors Corp now majority owned by the U.S. Treasury, for around $4 billion.
RBC and Ally both declined to comment on the matter, but analysts speculated that a sale, whether to the Royal or another Canadian bank, is likely.
* Canadian National Railway Co's third quarter result came in slightly ahead of expectations. But the country's largest railway also warned it was expecting a "challenging end to the year" given the uncertainty in the broader economy and some rising expenses that will likely carry on into 2013.