Stop the device (using the system tray icon) and disconnect it from the machine. Go to Device Manager and uninstall the device.
Reboot...then power the machine OFF.
Plug your device into a USB port on the back of the machine. Use a different port than was used before.
Power the machine ON.
Windows should detect and install the device automatically and should (hopefully) assign it a new IRQ. See if this allow the machine to run normally.