If you have not had your windows maintained in the last 10 years, we really need to talk.
 

First off, If they are caulked, or painted shut, it is highly likely that they have started to rot due to trapped moisture.  I see this constantly, and many are beyond repair.
 

Secondly, if they are operational, you are probably venting your heating and air conditioning out the tops and sides, to the point that you are wasting a very large amount of money, and still are not comfortable.
 

You will be surprised at how inexpensive it is to make them operational and add insulation.  In the worst cases, the charge is less than a tenth of window replacement.