What should I get to desolder components from random boards
Neither is particularly useful for desoldering all the components from a board.  Desoldering in general is not something easy to do in large amounts, but sort of a "here and there" type thing. Sometimes, an element of a board needs to be reworked, and tools like that can help, or maybe a hot air station would be more useful for your special case.  There are also a variety of different devices that would supply you with vacuum, like this.  Without knowing exactly what you're trying to do, and why, its tough to be more specific.