Maybe use the tactics developed in WWII? I don't know how labrynthine the cities and towns in Iraq and Afghanistan are, but urban warfare is still urban warfare.
Don't really know what's being talked about here, but I just popped in an I might as well respond to this.
So, the thing is, Iraq/Afghanistan and a hypothetical invasion of Europe are two different things.
In the Middle East, we are fighting insurgents inside a nation, with that nation's consent. Urban warfare becomes much more tricky when the people you are trying to fight are also hiding as citizens that you are (most of the time) trying to protect.
A conventional war in Europe, however, is another affair entirely. Things become much easier when your enemy actually has non-combatants and an industrial base that they need to protect. In a conventional war, fighting would be brutal and drawn-out. However, there would be little to no risk of civilian casualties, because your enemy would have evacuated most-if-not-all non-combatants. At the very least, they would be in uniform (assuming we're following the constraints of the Geneva Convention, IIRC)
E: What I mean by that last sentence, is that if there is a large pool of non-combatants in the city (more likely than I think now that I think about it), they will at least be uniformed enemy personnel, rather than plainclothes normal-looking citizens.
So no, urban warfare isn't urban warfare.