My Excel 2007 spreadsheet has 900,000 rows and 8 columns.
All of the cells contain data (no formulas).

When I click on the file-name and click OPEN, the status of the OPEN
process is displayed on the taskbar. After the green indicator goes
all the way to the right of the status box, the only thing displayed
on my screen is the hourglass symbol. Why isn't the spreadsheet
being displayed on my screen?

Windows Task Manager shows:

In the "Applications" window: for Microsoft Excel: "Not Responding".
(In fact, "Microsoft Excel" is listed twice).

In the "Processes" window: the "Mem Usage" for Image Name EXCEL.EXT
varies from 30,000 K to 200,000 K.

In the "Performance" window:
CPU Usage varies but is less than 8%
PF Usage varies but can be as high as 1000 MB
In the "Physical Memory (K) section:
Total stays at 514116
Available varies from 2000 to 100000
System Cache varies from 600 to 40000