you can change the size of the details section by rigth clicking the details section,and clicking on the properties ,go through the properties u will find the property that has to do with the size,alter it.
another method is by expanding the length of the detail section in the design view of the form or report,
for your second question,on the on load,or open event of the report,try the 2,1 will work.
enter the following code lets assume the field name is (status) then typpe the following code
if isempty(status) then status.visible is false.