I'd say flat files alone (so this excludes bdb etc.) are harder to handle than a proper database and SQL is easy to learn anyway.
Any languages are fine, depending on how do you want to develop your software. For a medium to big scale system, you could use JSP+Servlets+Java Beans with a simple db, such as MySQL, or PHP + MySQL/PostgreSQL or ASP/ASP .NET.
If you are familiar with Java, obviously the first choice would be better, if you are from a C/C++ background, PHP is an easy transition and if you are from a VB background, ASP would suit you fine.
Updated: need suitable language do FYP, Changed FYP Title...