[Interl0per]

I'm using Mint 13 KDE (Ubuntu 12.04 LTS), give that a shot. KDE has a netbook mode which I use on mine, as for your battery issues, netbook batteries are usually around 2200mAh which is half of a typical laptop battery. However, replacement higher capacity batteries for netbooks are a lot cheaper than laptop replacements, so have a look at replacement higher spec batteries. You will usually get 5400, 6600 and even 7800mAh replacements for notebooks.

Also regarding 'lightweight' desktops, after lots of experimentation, I have seen very little difference with 'lighter weight' DE's compared with a few of the more modern ones, KDE is very efficient these days and whilst I don't like Gnome 3, it's not too bad either. I don't think you will see much difference to be honest. Best just to get a bigger battery.