I’m posting this here just to give it a little more Googlability in the hope that people might find it more easily than I did.
If you install Ubuntu on a HP 510 or HP 500 laptop you’ll find that the touchpad doesn’t work. Then you’ll find this page which details a fairly crufty kernel hack to get the touchpad working. It also explains how to select the native 1280×800 screen resolution.
Having done that you’ll reboot and find that the WiFi isn’t working. If you’re really lucky you’ll then find this thread that explains how to fix the WLAN.
Or you could just follow those links. Now if I could just get DHCP working on the WLAN I’d be happy…