Dear firduck,
if you have seen
www.cic.gc.ca, then probably you have assessed your self for the eligibility.
Assuming that you are eligible and you apply now under FSW class to CIC London office, then it is going to take more than 30 months in London to finalize. In that case your wife will be able to get British Passport after two years.
Other quicker options are job offer/work permit and PNP. Since you have a britich passport, you can visit Canada and try your luck for workprmit. Then you can also get Provincial Nomination.
Again best advise is
www.cic.gc.ca. Do some research and look for different options. Because you are the best judge of your available resouces.
Thanks
Cool