Excel 2007 : Data Table in Chart has Incorrect Labels & Will Not Allow Zero's to be Charted as "Gaps"

When I created a chart from a table and chose the option to add a data table to the chart, the resulting data table has the column headings reversed (not the data, just the headings). The chart data table shows the data in the correct order, but the Dec11 data has the heading of Aug11, the Nov11 data has the heading of Sep11, etc.

Also, I only want the graph to reflect data where there is a month label; at a minimum, not show the zero's. But when I select "Gaps" in the Select Data box, it still shows the line graph starting at zero rather than starting at the first value.

The data and resulting graph are attached.

Thanks for any help!