'''Yes''' ''- pull the Hard Drive, & put it in an external case'' you can then access the files (even transfer your entire user account) to a newer Mac. via [http://pondini.org/OSX/SetupOther.html|Setup Assistant or Migration Assistant].
Or, if you know the location of the data you wish to retrieve you can recover just that data manually via drag & drop. ''Merging an old and new email messags/addresses vary and can be complicated depending upon your email client (application).''
'''Old OS 9 apps will not work on brand new Macs''', ''but will work on Macs of a certain age.''
''If this answer was helpful please '''remember to return an mark '''it Accepted.''