I just got a more snappy performance improvement on my Ubuntu Feisty Fawn after tweaking my ext3 system configuration. The complete tutorial is from UbuntuGeek with the title how to get the most out of your ext3 and ReiserFS file system.
Since the tutorial is using VI as file editor, I suggest you to read a short introduction on Vi before tweaking the ext3 file system configuration following the tutorial, unless you are familiar with vi.
If you don’t want to use Vi and preferring to use GUI, you can use gedit respectively.
sudo gedit /etc/fstab