Hey , rat. I had the same gripe and didn't see anything in another forum topic or the Help files so I took a shot in the dark. I don't know if this is helpful, but after one experimental run it seems to be a work-around.
I use a Brother monochrome laser for my default printer on Windows, so I'll spare you the processes specific to setting my preferences. Short version is - Make the appropriate settings in your printer's preferences as default (no footers or headers, margin size etc.). Then use Cntrl+Shift+P (instead of Cntrl+P or the Opera menu) and it goes straight to the system dialog, bypassing the preview altogether.
If you are printing only part of a web page such as a recipe or an account statement where you click the print command link on the page, you have to let the preview load and then click on "Print using system dialog" down at the bottom of the Print Preview's control panel. Otherwise it might print the whole page.
Worked for me.
Good luck!