Try AIDA/Web, a Smalltalk Web Framework, it is known for its simplicity, not to mention of the elegance of Smalltalk!
To stay simple, the additional database like MySql is not needed, because the Smalltalk image is a capable object database by itself. Later when your needs arise, you can decide to go relational, or even better, stay pure OO and choose a Gemstone/S object database.