Thank you both for answering. However, your answers are a bit too technical, as are the Help-pages. Anyhow, it now seems to work, and I got it all transferred by doing as follows:
I copied all the files and entire folders mentioned on the About-pages, and copied them as replacements on my new installation on my new PC with Windows 8. As to Opera Mail, the email server returned"Applicaton-specific password required: http://support.google.com/accounts/bin/answer.py?answer=185833(Failure)", which I slowly understood had to do with 2 step security system. I had to go to that page at Google and get a new security code to use as password in Opera Mail.
EF
