The only way you can get IMDb to remove a Title is to show that it does not meet the eligibility requirements for listing. The requirements are much looser than they were a few years ago, and if a film was released on Youtube there is a very good chance that it is listable.
IMDb is a database of credits, and lists the facts. It is not a Resume site where you can decide what data you wish to be recorded (although they do offer a Paid Resume page you can set up as you wish). You need to understand that this is not your page in the sense you can control it; it is IMDb's page about you.