Having spent yesterday setting up a new laptop to dual boot Windows and Ubuntu, Ubuntu works far, far better.
Windows needed drivers installing for everything from the network interface up. And I'm still having troubles with the network - I can use wifi fine, but the wired connection refuses to pick up an IP with DHCP.
Ubuntu on the other hand needed a single change to the boot parameters to make screen brightness adjustments work. (Windows also needed a driver for this). Otherwise it works perfectly.