Thanks for the input guys. As I suspected, this thing came loaded with animals, two of each, on an ark. Like I said, my PC / Windows knowledge is a little thin when it comes to things like this. My reason for asking of course is what gdiza said. Virtualising Ubuntu on my mac is all very fine and well but it fails to recognise those USB Modems and therefore I have no serial ports for these. By setting up this old box with Ubuntu, I can try and port something like mAcme to Linux (please, no promises yet - I will try).
Now I know how much to offer for it - R300 you say is fair? Excellent...