if you have not tried it mozbackup can be downloaded from here
it can backup and restore settings and email
before the locations of profile can be seen you will have to view hidden files, click on "my computer"/ then "tools"/then "folder options"/ then "view"/ then put a dot in the (show hidden files and folders )make sure that when finished you reverse and put the dot into ( do not show hidden files and folders )
full details of the Profile storage and locations can be found here
Just browse to C:\Documents and Settings\Your user name\Application Data\Thunderbird\Profiles\
on Windows XP/2000 or C:\users\[User Name]\AppData\Roaming\Thunderbird\Profiles\ on Windows Vista, and the rest should be obvious
* On Windows Vista/XP/2000, the path is usually %AppData%\Thunderbird\Profiles\xxxxxxxx.default\, where xxxxxxxx is a random string of 8 characters. .
* On Windows 95/98/Me, the path is usually C:\WINDOWS\Application Data\Thunderbird\Profiles\xxxxxxxx.default\