[wlug] Update problem

I have a very strange problem. I had Ubuntu 9.10 working well on my desktop - after updating to 10.04, it would not recognise my mouse or keyboard - they are not usb, they are the older plug in types (?ps2). When I plugged in a usb mouse, and rebooted, both the usb and old devices worked intermittently. I then plugged in a usb wireless keyboard and mouse and all was well for a while but now both have ceased to function - I just get a stationary arrow and no way of accessing anything. They all work perfectly if I boot into windows as this is a dual boot computer. Any ideas?