Any advice on the best way to clean mirrors. W are non smokers, however,it seems if there is a film on my mirrors. Also, any ideas on the best way to clean windows. My windows are old and have to be removed from the outside

I once heard that the best way to clean e.g. like a car window and mirrors is by using a newspaper.
First wet with a sponge, then dry with a newspaper. Ive used it on my car windows and it works wonders :)

Ammonia works great. A mixture of rubbing alcohol and ammonia just really cuts through about anything. A cheap and effective fix.

Some folks polish with old newsprint. Not a bad idea - the newsprint gives enough lube to make it easier to polish whereas paper towels are more work. Old towels work well.