No problem. Just killing time. ;-)

You can suppress display of zeros for any particular spreadsheet.

File: Options: Advanced

Go about half way down to Display Options For This Worksheet. Make sure the worksheet you want is selected in the dropdown. Uncheck the box for Show A Zero In Cells That Have A Zero Value.

Otherwise, if you want to do it by equations, change the first to be:
=IF(OR(D3=0,E3=0),"",D3*E3)

If you don't have negative numbers:
=IF(MIN(D3:E3)=0,"",D3*E3)
or
=IF(MIN(D3:E3)>0,D3*E3,"")

Or you could conditionally format any cells that have a zero value to have the same font and background color.

Lots of ways to do this. The first is preferable. Less moving parts. :-)