Elementary OS, just because it's Debian/Ubuntu based so it's nice and easy to use, but it's also fairly light-weight. I think because it's quite a nice looking

Elementary OS, just because it's Debian/Ubuntu based so it's nice and easy to use, but it's also fairly light-weight. I think because it's quite a nice looking distro as well, it just makes work a bit more of a pleasure. I feel sorry for the others still using Windows 7!