For the keyboard: What do you mean you can use it until it asks for your username? What can you type before you log in?
For the mouse: I have an Microsoft Explorer mouse and have the following in my XF86Config file. If you are using X 3.x you should use something similar. If you are using X 4.x let me know and I will give you the correct config. Also, I would recommend imwheel if you would like to use the scroll wheel.
# For wheel support - can not be used with Emulate3Buttons
ZAxisMapping 4 5