if working with wooden frames, you should check out RL how this is mostly handled.
The main way for wood, is working along the texture, just like this:

Also try some bump on the seams on the edges where the wooden parts come together!
for your wooden material try a phong with some exponent map and some low Exponent values, by this you get some very subtle bumpy effect, that sells you image better
Also think about how to open your window... if possible some extra detail (openening handel, metal bearing etc.) would help here too
but anyway, so far so good for being n00b
BTW: I also hope you use some exit portals for your windows to keep rendertime low!
