SQL Server and MSDE provide a far more reliable database engine that the Jet engine provided with Microsoft Access.
The Upsizing Wizard provided from Microsoft is the easiest way to convert an Access database to SQL Server or MSDE. The Upsizing Wizard preserves database structure, including data, indexes, and default settings, and automatically converts Access validation rules and default settings to the appropriate SQL Server equivalents. The Upsizing Wizard also maintains table relationships and referential integrity after you upsize.
for more information on the Upsizing Wizard and step by step instructions on using it to convert your Access database to SQL Server or MSDE, visit http://support.microsoft.com/kb/q237980/.