php/asp/netdynamics

I'm looking at using the above for a web application on SQL Server and Informix databases, running on IIS. It needs to be customisable - the main concern is that I need a client to be able to select which fields to show on a page, so one might want day totals to show, another may want day and week totals, another just week totals. Could anyone tell me which technology would lend itself to solving this problem and the best architecture to use - application variables/database fields? Can you use php to create COMs? Appreciate it Russ