Typical........could they not have left that option on the screen....
It looks as if you will have to edit your prefs:ini file manually.
To do that, open the prefs:ini ( it will open in Notepad) and scroll down to you get to "startup dialogue" and change the last digit on the row of numbers to 0 (zero)....the page will look like the attached ( which is already set to 0 ).
When you have done that, save it
How to find the .ini file. In mine the path is c:/ documents and settings/owner(or you name or your identifier)>application data>opera>opera>opera prefs.
To see that full path you may have to reveal hidden files and folders.......in Windows Explorer...tools>folder options>view>show hidden files and folders.
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