if your deploying a database with an application i'd recamend useing a ms access database because sqlsever(msde) databases requir the server to be installed and configured on the destination machine where as access databases are self contained files that can be deployed with applications
luckily with .net switching a program from one database to another is easy when the tables are the same all you gotta do is change the DB connection(s) and it's done
I do have MSDE installed on the client. I used the MSDE toolkit. It works great for installing MSDE and .NET framework if not installed on client before installing the application. I just can't get the Installer class to work. Plus, I like the security of the MSDE database.