Adding new rows to an Excel spreadsheet
 

I am working on a 10 column Excel (Mac 2004) spreadsheet originally created
by someone else. I need to add new data while retaining the original info.
When I attempt to add a new row across all of the columns, a thin, gray
frame/window appears around a section of the spreadsheet and limits the new
row to only 3 of the 10 columns. Is it a filter? How do I remove it without
losing the data in the section it surrounds?