So I am using the wood stairs to design my walls and corners in one room a certain way and wanted to know which one looked better, the normal oak or the dark oak stairs
If you mean using either spruce or dark oak and oak, I'd go with the latter as it gives the interior some variation of color. If you mean using either oak or dark oak, that depends on your palette, but I would generally opt for oak, as it isn't a color which 'pops' as much as dark oak, which isn't something you want a wall to do in most cases. This, of course, is ultimately up to you and however your creative style dictates you proceed.
looking at the two screenshots you gave I felt the all spruce was too monotone whereas the other example felt too busy as it had 3 kinds of wood all together (spruce,oak, dark oak). I personally would go for 2 woods to give it more balance so either spruce and oak, or spruce and dark oak. Obviously my own personal preferences so take or leave as you like Hope that helps
It depends what you like more. I personally think the dark oak looks nicer. The deeper browns of both spruce and dark oak blend easier than oak and spruce do. However if a look of highlighting is what you're going for, then by all means, go for oak, as it stands out more.