It looks like there's quite a range of opinion on olive and flaxseed oils. 
Ginny, Carrie and I use olive oil, Cordain and Enig say it's OK in 
moderation, whereas Mercola advises against using it at all. I do know 
that the omega 6/3 ratio is not great in olive oil, and that the fat from 
pasture-fed meats and flaxseed oil have better ratios (along with fish 
oil, but who's going to use fish oil as a cooking fat on meats and 
vegetables? :-) ), but I do use olive oil (in moderation) along with 
animal fats in cooking and use flaxseed oil in cold dishes like salads 
(but don't cook with it). Whereas Mrs. Centa also uses flaxseed oil in 
cooking and Ginny doesn't consume it at all. So we have quite a bit of 
diversity on flaxseed right here in this forum. 

I do a lot of cooking without using any added cooking fat beyond what's 
already in the meat or fish--and people even comment on how strange it is 
that I use so little added cooking oils or fats beyond what's already in 
the meat. When using olive oil, I've been using the more stable light 
olive oil for cooking and extra virgin mixed with flaxseed oil (or 
straight flaxseed oil) for cold dishes. I know that cold light olive oil 
has a less healthy profile than cold extra virgin olive oil, but I figure 
it's safer to cook with the more stable oil. I haven't researched olive 
oil much. If it turns out to be safe and effective, that new Nikken 
cookware might reduce concerns about free radicals in cooking oils--thanks 
for the tip, Ginny. Here is a link I found on it: 
http://nikken.com/newproductshome/default.asp?
category=cookware&section=technology. 

I occasionally use canola oil, but I'm not here to defend or promote 
something I am ambivalent about and rarely even use (I didn't use to use 
it at all, but am less of a purist than I used to be :) ). Besides, Todd 
Moody has made better arguments in defense of canola oil in this forum 
than I ever could and he doesn't even use it at all! :) I merely guessed 
that someone might have used it because it has been mentioned in this 
forum quite a bit, it is in The Paleo Diet book, and I didn't really think 
much about it before I wrote my question. It sure stirred up some 
interesting discussions though, which may be for the good, because the 
number of posts has been dwindling.