What's your recommendation for PHP MVC frameworks?? i tested Codeigniter and it seem easy to use....

I am not a full time developer, but I do have some customers with backends, etc…My intention is to migrate some of old php code to PDO but I am now wondering if I should move the code to MVC....any recommendation?

MVC is an architecture, while PDO is a database class. You can move to MVC and use PDO. They are not mutually exclusive.