clean upgrade, what is the minimum

[p.echols at comcast.net]

Greetings all:

I am planning on upgrading my netbook by doing a clean install and restoring portions of /home from backup.  But my intention is to restore as little as possible to eliminate years of cruft.  From my /home/patton directory, all I think I need (aside from documents of course) is my email .thunderbird and .ssh for my various keys.  In another thread, it was suggested to include bits and pieces from /etc and /var.  What would I need from those directories?  Is there something else I'm missing?

Thanks

PE