Are you printing the form from the Web Browser? If so are you referring to it printing the entire browser window so it includes the area outside of the form page boundaries?
FormsCentral doesn't have any support for printing from the browser, meaning we don't do anything special, the browser simply prints the page To print a forms response, in a Paid level subscription, you can "Download Response as PDF Form" which gives you a good PDF to print from.
I do not know if this would be considered "from the Web Browser". We log into the Adobe Forms Central, click on the form we want to print and then click the printer icon at the bottom right had corner of the Adobe screen. We tell it to print one copy. When this copy prints, all the questions are on the left in dark grey boxes (with white lettering for the questions). The grey boxes use a lot of black ink to print. Can we get rid of those grey boxes, but keep the questions?
I am not positive what you are printing from but I am thinking it is from the View Responses tab with a response row selected and then shown in "Detail View" and that the column of field names has a dark grey background...
To change the color of the column headers select the row of headers (do this by clicking on the first dark grey header field and then scroll to the last one and shift+click on the last one), then in the "Text" tools change the text color to Black and the Fill color to white:
(Selected the header cells)
Changed the text/font color to black and the fill color to white
Now you can see the detail view does not have the dark grey.