Are you using a Bump Map on the wall to the left and the step wall there? 'cause they don't look right, you should try using Normal Maps instead, also change the map on the step wall it looks the same as the house wall.
About the windows all you need is an HDRI Environment, i can't post links yet in here but if you google it type 'HDRI Environment' and you'll see one of the results called "HDRI Tutorial : Xedium3D" this one is fairly simple to follow.
I hope this helps you.