Does anything else work thru' USB, ie. a printer? If not, then the USB driver is probably not loading. Check in Device Manager (right-click My Computer, choose Properties and hit the Device Manager button found under the Hardware tab at the top.) If there is a yellow triangle next to the USB controller, double-click on it and use the Driver tab on the next box that appears to uninstall the driver. Reboot and Windows should recognise a new hardware device and install a driver for it. Then you may want to look for an update via click here or the website for your friend's motherboard manufacturer.
If USB is okay, then connect the mouse and k/board to the PS2 sockets via USB to PS2 adapters. This should have come with the peripherals, but can be sourced from a good PC store.