doccarnby: I don't have a Xbox controller, and honestly never plan on getting one.
For better or worse it is pretty much the default PC gaming controller at this point. I'm not telling you to get it, that's your choice obviously, but it saves a lot of headaches when you want to use a gamepad.
doccarnby: And the mouse aim mod only works on cracked Euro copies? That's... absurd.
Last I heard, yes. That might have changed eventually, I haven't kept up with the RE4 modding scene (and that's a main reason I didn't offer you links).
doccarnby: And my computer's not that great, but I've heard that a lot of the graphics mods don't really affect performance, is that true?
Well the texture mod would only hit your VRAM and unless your GPU is ancient I doubt it would be a big deal. The lighting mod is probably insignificant.