” it told me to run ‘rmmod xpad’. After doing that and manually running xboxdrv”

Yes you need to black list xpad so there is no conflict with xboxdrv

be sure to follow https://github.com/retropie/RetroPie-Setup/wiki/Setting-up-the-XBox360-controller instructions.
I prefer method 3 emulators don’t lag that way.

if you follow method: http://www.libregeek.org/2014/03/13/retropie-installation-guide-for-the-raspberry-pi/
be sure to add –dpad-as-button in the script if you wish to you both dpad and joystick in you emulators although with this method I couldn’t get a wired and wireless xbox controller to work at the same time. the one above works amazingly.