Although you have been given quite a few answers Ill give ya my opinion.
1. If you want to stay with Ubuntu then move to a lighter interface like Fluxbox , Enlightenment or whatever. Secondly waste all not essential stuff. Also there should be a post of mine linking how to strip Ubuntu down to a bare minimum ., Wasn't done by me but the author is kmandla a moderator on ubuntuforums. Just do a google search for it or on the forums.
2. In the end you are going to be doing enough work to keep a bare minimum Ubuntu that you are better off going with a light distro . Also as suggested above I would recommend going to Arch Linux as well and use whateverya want.