What are the differences between "Rip Van Winkle" and "The Fall of the House of Usher"?
Washington Irving and Edgar Allan Poe along with Hawthorne and Melville make up America's first great quartet of fictional writers. All four used similar romantic elements in their work and focused on similar themes. Irving and Poe are probably considered very similar because they both utilized distinct Gothic elements in their stories, including dark and mysterious atmospheres and characters.
Given this relationship, I think it is necessary to contrast "Rip Van Winkle" to "The Fall of the House of Usher" on a scale of Gothic elements. "Rip Van Winkle" contains less of the dark Gothic elements than does "The Legend of Sleepy Hollow" and certainly less than "The Fall of the House of Usher." Both stories include a romantic journey into the wilderness and both journeys lead characters into a tragedy of sorts, but Rip's journey ultimately ends positively for him. He returns to a new world and new life and escapes the plight of the wife who drove him to the wilderness in the first place.
The narrator in "House of Usher" cannot boast of a similar relief. His journey ends in the tragic deaths of two people and the narrator himself barely escapes with his life. Additionally, the characters in these two stories are very different. In the typical style of Poe, the characters in "House of Usher" are either physically or psychologically ailing in some way. Similarly, the narrator in "Rip Van Winkle" comes with an element of distrust, but the distrust is caused by a tone of satire rather than a hint of psychological damage.
Generally speaking, both stories are classic American Romances that contain Gothic elements. The biggest difference is that "Rip Van Winkle" lacks the tone of horror that "The Fall of the House of Usher" clearly possesses.