You say the rows with the total contain blanks in the first two columns, the other rows do not. So if this is your criteria the query is quite easy:

select *

from dbo.TableX

where col1 = '' and col2 = ''

Try this select to check if it returns the rows you want to delete. If so replace the "select *" by "delete" and these rows will be deleted.

delete

from dbo.TableX

where col1 = '' and col2 = ''