MS SQL questions

Hi, I'm using MSSQL for my database application and not yet ready to transfer my data to MySQL because of the file limit. We have a very huge database. MS SQL 7 Windows2000 Adv. Server IIS 5 PHP 4.3.0 MySQL with MyODBC Visual Basic & MS Access as client We are developing a web application to access our data from MS SQL.. what are the softwares or driver do we need? Can somebody give me some code samples? I tried to use mssql_connect() syntax but it returns some error.. Thanks. Calixto Ong II