Ah yes, the iconic black and white image of Mickey Mouse as captain. So much of Mickey's personality is shown is just this opening scene. Here we have a lovable character that is very relatable. His design has changed from his appearance in Plane Crazy. Besides gaining shoes (yet still gloveless), Mickey's eyes have turned to oval buttons.
Steamboat Willie is another Mickey cartoon which isn't up to Disney's present, family-friendly standards, though it's important to note that it was perfectly fine in 1928. While it is void of any racial stereotypes, it does have a scene featuring tabacco chewing.
Steamboat Willie remains one of the most important cartoons in animation history today. It was voted #13 of the 50 Greatest Cartoons of All Time and was even selected for preservation in the National Film Registry. It's not the greatest Mickey cartoon ever made, but it is very entertaining.