In a frugal install, opera can be very small on backup. There are only 5 or 6 files out of the 3.9M that need to be saved. (This assumes you leave the mail on the server if using mail client.)
bookmarks.adr
wand.dat if used
operprefs.ini
contacts.adr
speeddial.ini if used
mail/accounts.ini
I copy these to another directory, and let TC blow away .opera-11 using .xfiletool.lst. Before starting opera, just create the .opera-11 directory with these files. An alias command works well.