It would be "Valon ja pimeyden lauluja" instead of "Valon ja pimeyden laulut" - the latter is "The Songs of Light and Darkness" while the former equals "Songs of Light and Darkness" without the definite article. "Lauluja" also sounds prettier. Furthermore, "Valon ja pimeyden laulut", while not grammatically wrong, sounds clumsy as a title.. something like "Kaikki valon ja pimeyden laulut", which translates to "All the Songs of Light and Darkness" sounds better (while of course changing the meaning).
Uhh, kyllä kiinnostaa ja mielelläni olen pystyessäni avuksi, mutta aika on tosi tiukilla. Pitää miettiä hetki!
--Eino