Well I mainly know about the Ostfront and the Western Front, not that much about the Battle of the Pacific and to a lesser extent, the Battle for the Atlantic. But it was such a massive war, and in some cases, a new kind of war (ME-262, anyone? And what about the Vampir, and the SdKfz 251/1 that supported Panther tanks that was equipped night vision devices?) that you'll learn something every time you talk about it.
Also, as I said, "correct me if I'm wrong". Thanks though!