I undestand ubuntu is easy but as some one stated earler gnome is heaver than say lxde or xfce....lubuntu is lxde and only needs 128 MiB of RAM and all the apps are not as heavy so you have google instead of firefox,....
were ubuntu with gnome needs 512mb....plus some of the apps can be heavy...

Iv ran the 2 Oss and there was a big differnece in speed this includes start up and apps running....so what Im saying is wouldnt the nokia n900 benefit from a lxde/xfce as its 2nd os for pc tasks?