Hmm maybe at release there were some confused fans but I doubt that has hurt its long-term legacy. Here's my pitch:
An accident at a military base opens the film. Hulk is seen tossing soldiers around before jumping away and escaping the complex.
Next morning, SHIELD is allowed to invesitage the incident. There is a briefing scene where they go over the basic origin details. Ross explains that Banner was trying to create a super-soldier ("You mean like Captain America?" someone could ask). Fury orders Black Widow and Hawkeye to help General Ross track down and capture Banner. As the film goes on, Black Widow has a few close encounters with Banner and starts to sympathize with him. Fury begins to question the military's motives. Banner experiments with possible cures for his condition, eventually meeting with Samuel Stern. An accident occurs and the treatment fails.
Later on, Hulk is in a building as it starts to collapse following an epic battle with the military. Hulk notices Widow is still inside and, instead of fleeing, shields her with his body before bursting out of the rubble. Widow confers with Fury and he decides to use SHIELD's resources to help Banner stay in hiding "until he is needed."
I see it as a mid-budget horror film with Hulk as the monster. PG-13, under 100 minutes.