What's the meaning of the Collation Code (blank, 90, 100, 110) in SQL Server 2012
The one without the code is a version 90 (SQL Server 2005) collation, used by previous versions of Windows / SQL Server. The collation including 100 is newer (SQL Server 2008).

There's a bit of an overview of the differences in the SQL Server 2008 documentation, here, however it doesn't go into great detail.

If you're developing a new application, you may find that sorting is slightly more logical (particularly for unusual characters) with the 100 version. However, if you've got any other SQL Servers running with French_CI_AS, it might be better to keep it consistent with them.