ubuntu with your eyes closed. You will have to download some updates . lesser if you install a more recent version.
Ubuntu:Gutsy -
I consider the above guide the ubuntu bible. anything else, problems etc , google should help.

You will need to invest some time/bandwidth to get the stock ubuntu install into something usable ( mp3 , divx etc codecs, Java runtime , nvidia hw drivers, stuff like that ) , but once you do, you'll love it