Sim, você pode alterá-lo. Isso exigirá que você edite o registro para fazer essa alteração. Aqui estão as instruções passo a passo encontradas em Dicas de escritório .
WARNING: Using Registry Editor incorrectly can cause serious problems that may require you to reinstall your operating system. I cannot be held responsible for the problems resulting from the incorrect use of Registry Editor. Use Registry Editor at your own risk.
Quit all open Windows applications. On the Windows Start menu, click Run.
In the Open box, type Regedit, and click OK.
Expand the HKEY_CURRENT_USER sub tree until you see the following folder:
HKEY_CURRENT_USER \Software \Microsoft \Windows \CurrentVersion \Explorer \User Shell Folders
Select the "User Shell Folders" folder.
Create a new string value, by selecting Edit|New|String value from the rename it to "My Pictures" (without the quotes). After renaming it, double click it & set it's value data to the path that you want it to default too; e.g. "C:\Images\Jpegs". Note: If "My Pictures" string value already exists merely change it's value data.
Quit the Registry Editor.