I've recently inherited a medium-sized php site which is horribly coded. It violates every best-practices methodology, from MVC to DRY, is vulnerable to SQL-injection and everything in between.
I've visited the other questions and already put everything on a VCS and am considering the framework alternatives. However I'd like your opinions on a framework that lets me slowly migrate from the actual site to a framework controlled one.
Thanks.
Zend Framework would actually be the best choice in my opinion, as it has a great use-at-will structure and it is no full-stack framework like most of the others.
That means that you can start with migrating the model-layer first without having to touch the view or controller part. And even when it comes to the controller part, you could first put everything into controllers without having to rely on the router, so you could still use your old URLs.