The Task Pane only shows two templates, so if you open two different templates they'll replace the current items.
Or, you can edit the Registry (make a backup of the registry first!):
(instructions for Excel 2002)
1. From the Start button, choose Run
2. Type regedit then click OK
3. Click the + sign to the left of HKEY_CURRENT_USER
4. Open Software, Microsoft, Office, 10.0, Excel\Recent Templates
5. Double-click on Template1 or Template2
6. Delete the file name and path in the Value Data box
7. Click OK
8. Close the Registry Editor
