Database compatibility Level

Hello !

I'm creating a program with VB.net and Sql server 2008R2.
But I want that my application to run on other versions of sql server ( like 2005 , or 2008)

On Sql server management studio , I open the Database properties , and I can see an option " compatibility Level"

If I set the compatibility level to "SQL server 2005 (90) " , can I restore this database to sql server 2005 and 2008 ?

Thank you !