how do I do a complete reinstall

[myfarts>yourfarts]

remove all programmes and setting but keep everything in /home?

[ajgreeny]

That's right, though don't forget a lot of your settings and configurations are in hidden folders in /home so will be carried over. If you have a separate /home partition it makes life a lot easier as you can reinstall or upgrade to a newer version of ubuntu without a problem by just making sure you set the old /home partition as the new /home and ensure you don't format /home at that point in the installation process.

If you have /home on the /root partition, just back it up to usb disk or DVDs, making sure you also backup all hidden folders and files, and then restore home when you've reinstalled. It's dead easy really.

[zvacet]

You can make separate home following this (http://psychocats.s465.sureserver.com/ubuntu/separatehome) guide.

[Joeb454]

Please don't create duplicate threads

http://ubuntuforums.org/showthread.php?t=1029504