Hi Fabien,
The table of contents is a field. Many fields have two "views" - code view
where you see the curly brackets and stuff, and results view where you see
the value the field acquired when it was last updated.
You can choose to see onscreen either view of these fields and you can
choose to print either view of the fields.
In your case I think the fields are printing in code view. To make them
print in results view, do this:
In Word 97-2003 - go to Tools/Options/Print and in the "Include with
document" section clear the "Field codes" checkbox.
In Word 2007 - Click the Office button and select "Word options", click
Advanced, scroll down to the Print section and clear the "Print field codes
instead of their values" checkbox.
If you also want to be able to toggle between the views onscreen, you can do
this by pressing Alt+F9. Alternatively,
In Word 97-2003 - go to Tools/Options/View and in the Show section either
select or clear the "Field codes" checkbox.
In Word 2007 - Click the Office button and select "Word options", click
Advanced, scroll down to the "Show document content" section and either
select or clear the "Show field codes instead of their values" checkbox.
Regards.
Ed