[NTLUG:Discuss] Update files

[Michael Barnes]

I am running Ubuntu Squeeze on my desktop.  I think it is 11.3 or
something. At the time it was the latest LTS release.  After a couple
of years of regular updates, I see that I have gone through a  number
of kernel and other updates.  I'm sure these updates have left lots of
old files on my machine.  Is there any easy way to find out what files
are obsolete that can be cleaned out and free up some drive space?

Also, for LTS versions, why are there no updates for new versions of
Firefox and Thunderbird in the regular update packages?  I have to go
in and download the newer versions of Firefox and Thunderbird
manually, which is quite a pain.

Thanks,
Michael