I recently >posted a question in the general help and support about how the best way to find the last non-empty cell in a workbook. @Water was kind enough to help me find several solutions. During that thread we also posted a snippet that I find to be very useful. It was slightly off topic from the OP so I thought I would post it here so it has a home in case anyone needs it. That said, this is one way to delete all blank rows in a spreadsheet:
$oWorkbook.ActiveSheet.Columns("A:A").SpecialCells($xlCellTypeBlanks).EntireRow.Delete
The $xlCellTypeBlanks is a constant in the Excel constants include so you don't need to pre-define it. "A:A" is the range. So this would look for any blank rows in Col A and delete those rows from the workbook.
Hope somebody finds it useful.