have u learned light linking?
after you have explained your setup, its still my guess that is whats wrong with the scene.
in maya, you have the ability to assign lights to certain objects. again i am guessing, but it appears as tho all your lights are lighting all your objects. which is why you are getting that glow from inside your curtains.
select one of your lights and and then from the lighting menu select "select all objects attached to this light". if your curtains become selected, then deselect everything and select the "outdoor" lights and the curtain (select only one light at a time), return to the lighting menu and select "break light links". repeat this until you have changed your lighting so the outside affects the outside objects and not the interior objects.
you will then of course probably have to use additional lights and light links to finish your scene so it is properly lit.
as far as choosing which lights to use. . .i am still guessing myself. i almost always am using spot lights, but that is just because of what i am familiar with in the real world. i also like to use directional light when lighting for outdoors.
my suggestion would be to find a good lighting tutorial, so that you understand the difference between all the lights. as well, there are MR tutorials that will help. good luck!