have you tried running it directly from where you installed it?
sometimes when ive moved programs around, then forgotten to change the shortcuts for them, i'll get something like this, since the shortcut isnt pointing to the right file, if youve tried running it directly from where you installed it and this is whats happeneing, have you checked your permissions on the opera folder, mebbe one of the user permissions isnt quite right or something like that, is the account you are using the actual admin account, or just a child a/c with admin privieges