The age thing occasionally rears its head but in general there are jobs out there for all ages. Some schools actively encourage older teachers as they can give gravitas to the class so I certainly wouldn't worry about this side of things. For every school which might prefer a youngster, there are many more who don't mind either way.

And as for Dubai, in the Middle East schools tend to prefer one sex or the other so there's a chance that you'll women-only jobs as well.

Good luck anyhow!