Is it possible to reinstall Debian afresh and retain all the cutomisation and data from existing installation? I have done something stupid and messed up my Debian Squeeze installation. Now, the problem is I have enough data and sowftware installations which I don't want to repeat; is it possible to reinstall the OS and still somehow save and maintain data on my box? I have still not tinkered with the installation, I am just frustrated with issues and lack of time.

If you don't mind acting like a cowboy (and I have never tried this):

* Back up your `/etc` and `/home` directories (and next time, put your homedir in a separate partition). Do the same with anything else you changed outside those two directories.
* Do a fresh install.
* Restore your backups. The system-wide config dir, `/etc`, should be overwritten by this action. As for home, there's no risk at all restoring, assuming you are going to be logging in as the same username (and assuming that this was the first user you created during both installations).