Please do try these troubleshooting steps that may help.
- Start by connecting an external USB mouse and keyboard and see if both device will work or not.
- If both external USB mouse and keyboard will work proceed with uninstalling/reinstalling both drivers.
- Go to Device Manager and uninstall both devices (Mouse and Keyboard).
- Once done, reboot the laptop then test it again after the reboot.
- If they are still slow, run System Restore and bring it back to an earlier date or time when both device was working properly.
- Here's how to run System Restore: http/windows.microsoft.com/en-PH/windows-8/restore-refresh-reset-pc
- If System Restore will still not work last option would be to reinstall Windows itself.