Need to watch all the marvel films before watching The Avengers?

[Ashimar]

ok so the end of captain america, the end of Thor, and Iron Man 2 have scenes that tie it to The Avengers film.

so what i wanna know is...

Does The Incredible Hulk have scenes that tie it to The Avengers?
How many scenes in Iron Man 2 tie it to other marvel films? i saw the end
had Thor's hammer.... and in Thor there is a scene where the FBI or whatever thinks the robot destroyer
that the king from thor's world sent was actually one of Starks inventions.