On land (and arguably in the air) , I’d pick the Battle of Crete, the first mainly airborne invasion in military history. It was “the first battle where the German paratroops (Fallschirmjäger) were used on a massive scale, the first time the Allies made significant use of intelligence from the deciphered German Enigma code; and the first time invading German troops encountered mass resistance from a civilian population. […] After one day of fighting, the Germans had suffered very heavy casualties, and the Allied troops were confident that they would prevail against the German invasion. The next day, through miscommunication and the failure of Allied commanders to grasp the situation, Maleme airfield in western Crete fell to the Germans, enabling them to fly in reinforcements and overwhelm the defenders. The battle lasted about 10 days.”
At sea, I’d pick the cruise of (and the hunt for) one of the German merchant raiders – maybe the Pinguin (a.k.a. Raider F), the most successful commerce raider of the war. (The story of the raider Atlantis has already been put on film in the movie Under Ten Flags.) The climax would be the single-ship duel between the Pinguin and the British heavy cruiser Cornwall. The Cornwall wasn’t too badly damaged, though, so the fight wouldn’t be as dramatic as the one shown in the movie The Battle of the River Plate. So, come to think of it, a better choice might be the Kormoran (Raider G), Germany’s largest merchant raider, which sank ten merchant ships and captured one more. Kormoran engaged in a single-ship duel with the Australian light cruiser Sydney, which resulted in the loss of both vessels, so this would be a dramatic battle to put on film and the result would be similar to the conclusion of the classic movie The Enemy Below in which the destroyer and the U-boat end up sinking each other.