The choice of colour for the windows of any house depends solely on the personal tastes of the owner of the home as well as the position and the architectural style of the window. This means that no colour can be truly called the best or perfect one for your windows.
This blog has a variety of designs and painting ideas that can help you get inspired while looking for designs for your windows. You can also check popular websites such as YouTube and Pinterest for more ideas.
The choice of colours used for windows in India varies a lot due to regional and climatic differences. Regardless, neutral and pastel shades are all-time classic colours as far as interior design is concerned.
Wooden and earthy tones are often the most popular colours used to paint the frames of windows in a house. You can always experiment and mix and match the colours of the frames of your windows by considering the overall aesthetics of the house.