HPs 5780 All-in-one is listed by HP as Linux supported. So, try opening a browser and enter this in the URL box: http://localhost:631
That will get you to the CUPS admin page. Click on Manage Printers and try to add a printer. You may have to enter the root password to do so. Then go through the steps to configure your printer (which will include selecting the correct driver).
In fact, in CUPS, you can define several printers, each for a specific task, even if you have only one printer. Such as: draft greyscale, draft color, normal grascale, normal color, letter-quality greyscale, photo-quality color. You can set them up for portrait, and a similar set for landscape. Designate one to be the default.
When you are ready to print from an application, select the name you have assigned for the print quality you want.