If you want ages of battery life have a look at the EEEPC 1005HA. I can get about 10 hours out of mine, which I'm truly impressed by. It goes down if you're using it for music/videos obviously but it's still pretty good. A ten inch screen is big enough to see and it does make room for a slightly larger keyboard.
Downside, it's got a spinning hard-disc, not solid state, but I'm not sure that makes a lot of difference if you're stationary when you're using it, and of course no CD/DVD drive.
Upside it's got almost 160gb of memory, SD expansion slot, and best of all a factory reset feature, so if Windows goes wobbly, you just hit F9 on start up and it resets. It does mean you lose everything stored on C: But as the disc is partitioned, put all your data and installer files on D: and you're back up and running in about ten mins.
Happiness has 125 cc