Forget about video mode. Fireworks are light emissive, and in that case you actually have to lower the suggested camera exposure, usually overexposed due to the black background. Moving hummingbirds are not emmisive and are too complex for a camera exposure program to handle.
I have successful hummingbird shots, and as seasoned photographer I used to shot film in manual mode. With a digital SLR is quite the same, and your settings will depend on the overall light. Your goal is to have correctly exposed the bird, not the background. The camera will try to shoot the whole frame, and makes a compromise, so it will be wrong most of the times with this kind of shot.
Use shutter speed of 1/1000, 1/2000 or 1/4000. Any lower than 1000 will make the wings invisible. with 2000 the wings appear in motion but visible. My preferred setting is 1/4000, but it will depend on your camera.
Use ISO 400, 800 or 1000. The lower, the less noise in the pic.
The method of determining the manual exposure will depend on ambient light level, but there is a photo pro procedure I share here:
a) Set your desired speed and film iso setting in the digital slr, and set manual mode.
b) Place a letter size sheet of gray paper (try to get a 18% gray card in a photo store) in the place where you expect the birds, and set yourself in the place where you will take the pictures from.
(Better if it is sunny or cast, and the birds "stage" is not receiving direct sunlight, to minimize contrast)
c) Use your viewfinder camera meter, with a telephoto, to determine the best exposure (aperture) for the gray paper, ignoring the rest of the frame. It can be +-2 stops.
d)Take note of the setting and set the camera to that exact combination of speed/aperture next time you shoot your hummingbirds.
I have successfuly used ISO400, 1/2000, F4 on a sunny day, birds in the shade with a Canon 75-300 telephoto zoom at max zoom, with a Canon XTi body. To improve the picture, try to get a blurry background (a extra feature of a high aperture), and try to take a not so brilliant background.