Everything is in the profile directory, including keyboard, mouse,
menu, toolbar, searches and skin setups, ad filtering, notes, mail,
wand passwords, bookmarks, contacts, news feeds, usenet and irc stuff,
cookies, history, favicons, user javascript and so on.
The only thing you might want to backup outside profile is the stuff
you eventually have outside that directory (some side panels, opsed,
mhtsaver and stuff like that, which in my case is under /Tools under
the main directory). I usually rar the entire opera directory and
uncompress it after formatting. Opera doesn't use registry entries, so
the files are the only thing you might want to backup.
The url you talk about is at
http://www.opera.com/support/search/supsearch.dml?index=313
Regards