I wouldn't have thought it would matter.
I had a similar problem when I booked our flights from here to Manila with Malaysia Airlines. I mistakenly put my wife as Mr! Initially, I was told that it was impossible to change the ticket without a huge charge, but they soon agreed to do it for free.
After doing some research, I found out that the name on the ticket needs to match the name in the passport, but a British passport doesn't use a person's title, so it's a "grey area". I found lots of anecdotal evidence that an incorrect title doesn't mean that someone will be prevented from flying.
I would have thought that Ms instead of Mrs would cause no problem at all.
