Developing web application

I am observing small scale web application development for last few years. Certainly, php-mysql plays most biggest role in development. But choosing right tools for right project is becoming more off track. I have seen tendency to develop any web application with php-mysql where as it can be developed with php-sqlite. Simple template system can be used where as smarty is being called. In fact, total project code is more or less 100KB but 600 KB external code is being used in name of design flexibility. So, I am thinking to prepare a guideline to develop small web application (website presents company information, product information, contact information, interactive communication etc). Open source is a bless but we must know how to find the right one for our job. At the end it’s all about service and how easy the service can be provided.