your computer is not too old to accept a usb 2.0 pci card (providing you have the slot space). using usb 1.0 should still not amount to the time taken to fully "ghost" your kit. (10 hours).
make sure that you are not on the net, temp disable anti virus, and most importantly, close all other apps that might be running as this uses system and processor speed, hence slowing things down.
hope this helps
al.