On my netbook I'm using Chakra Linux. I'm a big KDE fan, but for KDE to be practical on a netbook the base has to be veeeery lightweight, as with Chakra. Gentoo or Arch would of course be lighter, but I'm not up for such an involved installation. I've previously recommended LMDE to people who do not share my tastes, but I haven't tried it myself. When I used Ubuntu, aside from hating Unity and GNOME, I got some really bizarre bugs and it felt sluggish.