Sure, I can help you with that! Here are the steps to set up a pop-up calendar for 2010 in Excel 2003:

1. First, you need to make sure that the "Developer" tab is visible in your Excel ribbon. If it's not, go to "Tools" "Customize" "Toolbars" and check the box next to "Developer".
2. Click on the "Developer" tab and then click on the "Insert" button.
3. In the "ActiveX Controls" section, select "More Controls" and then scroll down until you find "Microsoft Date and Time Picker Control 6.0" (or a similar version).
4. Click on the "OK" button and then click on the cell where you want the pop-up calendar to appear.
5. Right-click on the Date Picker and select "Properties".
6. In the "Properties" window, find the "Value" property and change it to "01/01/2010" (or the date you want to start with).
7. Find the "Format" property and change it to "3 - dtpCustom".
8. Close the "Properties" window and save your workbook.
9. Now, when you click on the cell with the Date Picker, a pop-up calendar should appear. You can use the arrows to navigate to the year 2010 and select the date you want.

That's it! You now have a pop-up calendar for 2010 in Excel 2003.