The Gospels are an entirely different genre than the Koran. Reading the Gospels does not lead one to an understanding of the Koran any more than a reading of the Gilgamesh epic would lead one to an understanding of the Koran.
No it doesn't, but reading both (and I have a book that does a side-by-side word-for-word comparison of the Holy Bible and the Holy Koran) and you'd understand that the Koran is based on the Holy Bible, which it is.